Table of Contents
In our previous lesson, we discussed some significant application areas of ICT, including:
1. Video Conferencing:
Benefits
2. Teleconferencing:
Benefits:
A mobile phone, also known as a cell phone or hand phone, is an electronic device used for making calls across a wide geographical area.
An electronic device designed to process information.
Fax machines, short for facsimile transmission, have been in use since before the era of modern GSM. They utilize scanning technology to transfer text and graphics between machines, making it an effective method for transmitting paper or document-based information.
An electronic banking outlet where individual customers, using their PIN numbers, can complete basic transactions.
Machines that dispense items such as snacks, beverages, lottery tickets, and consumer products.
A machine used for processing sales transactions and automated cash register functions.
Devices designed for voice transmission to reach a vast audience in and around a country.
A mode of transmitting information and events to people through audio-visual means.
When a computer is powered on, the booting process initiates, launching the operating system. Here are the steps involved:
Power Supply Activation:
System Initialization:
The computer conducts a Power On Self-Test (POST) to check the functionality of its hardware components.
4. Operating System Load:
1. Warm Booting:
2. Cold Booting:
Starting the computer from scratch following the standard power-up procedure.
Cold booting involves starting the computer from scratch. When you initiate a cold boot, the system undergoes a comprehensive boot-up process, starting from the point where the computer is completely powered off. As the system initializes, it performs thorough checks on its hardware components, known as the Power On Self-Test (POST). This ensures that all components are in proper working condition before proceeding. The entire booting process takes a relatively longer time compared to warm booting, allowing the system to perform a meticulous assessment of its hardware.
Once the system successfully completes the booting process, the operating system is loaded from the disk into the computer’s Random Access Memory (RAM). Following this, the Windows desktop is displayed, showing icons such as the computer, recycling bin, and internet explorer. Cold booting sets the stage for a fresh and complete system startup.
In contrast, warm booting occurs when the computer is already powered on and in an operational state. This type of booting is typically initiated to address specific issues without shutting down the entire system. Warm booting is faster compared to cold booting because it skips certain stages of the system boot process. It is commonly employed in scenarios such as making changes during system checks, resolving hardware failures, dealing with sudden power loss, or addressing issues that cause a program to fail in execution.
During warm booting, the system skips the extensive hardware checks performed during a cold boot, allowing for a quicker reactivation of the operating system. Despite being faster, warm booting does not provide the same level of thorough hardware verification as cold booting.
In summary, cold booting offers a complete and thorough startup process by turning on the system from scratch, while warm booting is a quicker method, initiated when the system is already running, often to address specific issues or make changes without a complete shutdown.
The Windows desktop is the visual interface where icons, the taskbar, and the background are displayed after booting. Key components include:
Within the desktop, users can create, delete, and copy files.
Running an Application Program:
Shutting Down the System:
The lesson concludes with students having the opportunity to correct their evaluation tests, ask questions for clarification, and summarize the key takeaways. Teachers encourage active participation to enhance understanding and clear any doubts.
Word processing involves utilizing a computer to input and modify text and graphics in documents such as letters, reports, and term papers. To engage in word processing, you require a computer setup and specialized software known as a word processor.
A word processor allows the creation of various documents like letters, term papers, newsletters, and memos, storing them electronically on a disk, and facilitating editing or printing.
Advantages of word processing over manual typewriters include:
In a word processor, there are two types of toolbars:
Creating a new document is a primary task in word processing. When you open Word 2010 from the Start menu, it opens a blank space based on a standard template with default settings. You can start typing right away or create a new document based on custom settings.
Saving a document involves storing it on a computer or other storage device for future use.
Steps for Saving a Document:
Opening an Existing Document:
Closing Your Document and Quitting Word 2010:
When you finish working with a document, you can close it and exit from Word. Ensure you save your work before exiting.
From the Title bar, click the X button, and the window closes.
To Close and Exit from Word:
From the Office button, choose Exit.
Tables help organize columnar information for various documents like forms, financial reports, and catalogs. Tables consist of rows and columns of data typed in cells, where the intersection of a row and column is called a cell.
Demonstrate how to open a word processor on a PC.
Create a document, save it, and print it for your teacher to review.
Students are allowed to provide corrections to the assessments given by the teacher, with the teacher providing support to guide them.
A presentation software package serves the purpose of showcasing information through a slide show format. It encompasses three primary functions: an editing feature for inserting and formatting text, a tool for incorporating and manipulating graphic images, and a slide show system for presenting content.
Examples of Presentation Packages:
Microsoft PowerPoint, as an illustrative presentation package, possesses distinct features setting it apart from other Microsoft products like Word, Access, and Excel.
Creation of Slides:
Each page in PowerPoint is referred to as a slide, defaulting to Landscape Layout with dimensions of 11” wide by “tall. Various presentation elements such as text, images, sounds, charts, graphs, and text columns can be added independently and modified individually.
Steps for Inserting Pictures:
Insertion of Video and Audio:
Special effects, like animations or movies (in GIF format), can be inserted to enhance presentations.
Slide Transition: Decide on speed, duration, and the triggering action for transitions during the slide show.
A slide show entails a full-screen display of each page in a presentation, serving as both a presentation medium and a stand-alone demo at trade fairs.
PowerPoint facilitates the creation of various shapes such as lines or objects like rectangles, ovals, and auto shapes.
Computer hardware is the tangible and physical collection of components that collectively form a computer system. These components are the essential building blocks responsible for the functionality of computing devices. Embodying a diverse range of devices, computer hardware includes elements that can be touched and interacted with directly. The core constituents of computer hardware encompass the monitor, mouse, keyboard, computer data storage, hard disk drive (HDD), and the system unit.
Within the system unit, various critical components contribute to the computer’s overall capabilities. These components consist of graphic cards, sound cards, memory modules, the motherboard, and various integrated chips. Each plays a specialized role in processing, storing, and facilitating the seamless operation of software applications. Unlike software, which comprises instructions and programs that reside in a digital format, hardware constitutes the physical infrastructure that executes these instructions.
Input devices serve as the conduits through which data is entered into the computer for processing. These hardware peripherals facilitate user interaction and data input, contributing to the overall functionality of the system. Examples of input devices include the keyboard, card reader, mouse, scanner, microphone, joystick, and other similar tools that enable users to convey information to the computer.
On the other hand, output devices are responsible for presenting the processed data to users or storing it in external devices. These hardware components play a crucial role in delivering the results of computations and operations performed by the computer. Common examples of output devices include monitors, printers, speakers, projectors, and other peripherals that convey information in a tangible and comprehensible form.
Together, input and output devices create a dynamic interaction between users and computers, forming a vital bridge for communication and data exchange. The seamless integration of these hardware components ensures the effective functioning of a computer system, enhancing its overall utility and user experience.
The primary function of the CPU is to execute mathematical calculations on binary numbers, but it also serves other purposes. The CPU encompasses various hardware components such as the motherboard and circuits.
Within a computer, the central processing unit (CPU) is the hardware responsible for executing the instructions of a computer program. It performs fundamental arithmetic, logical, control, and input/output operations for the system.
III. Memory Unit: Plays a crucial role in storing and retrieving data for the CPU’s operations.
In the typical CPU configuration, the ALU handles arithmetic and logic operations, while the control unit manages the overall operation by extracting, decoding, and executing instructions from memory. The control unit also provides timing and control signals, directing the flow of data between the CPU and other devices. In modern computer designs, the control unit is usually an integral part of the CPU with consistent roles and operations.
Memory in a computer serves as the repository for both data and instructions used in processing. It retains programs and instructions or data only for the duration of the program’s operation.
This type of memory is directly accessible by the CPU, engaging in constant interaction. It retrieves stored data, processes instructions, and executes them as needed. Primary memory, such as RAM (Random Access Memory), is volatile but swift. Within primary memory, there are two sub-layers:
(1) Processor Registers:
Located within the processor, these are exceptionally fast forms of data storage, containing a word of data, typically 32 or 64 bits.
(2) Processor Cache:
Designed to enhance computer performance, the cache links fast registers to slower main memory. It swiftly loads duplicated information actively used, operating faster than main memory but with limited storage capacity.
Primary memory serves various purposes, including:
(1) Input and output operations.
(2) Text manipulation and calculation operations.
(3) Logical or comparison operations.
(4) Storage and retrieval operations.
(1) RAM (Random Access Memory):
Provides volatile storage; as long as it receives power, it retains stored data without requiring special regenerator circuits.
(2) ROM (Read Only Memory):
Retains data even when power is cut. Unlike RAM, ROM only reads and does not accept instructions from users.
(a) Programmable Read Only Memory (PROM): User-programmable for converting critical operations into microprograms.
(b) Erasable Read Only Memory (EROM): Can be erased and reprogrammed after exposure to ultraviolet light.
(c) Electrical Erasable and Programmable Read Only Memory (EEPROM): Reprogrammable using special electrical pulses.
RAM (Random Access Memory):
Elaboration:
Random Access Memory (RAM) is a type of memory that allows the computer’s processor to access stored data in a non-sequential manner.
Accessibility:
RAM is easily accessible by the processor, enabling swift retrieval of information stored within it. The processor can directly interact with and retrieve data from RAM as needed.
Working Type:
RAM facilitates both read and write operations on the stored information. This means that data can be both retrieved and updated during the execution of programs.
-Storage:
Primarily used for temporary information storage, RAM provides a quick and dynamic workspace for actively running programs. However, the stored data is volatile and is lost when power is cut.
Speed:
RAM boasts faster access speeds, significantly contributing to the overall speed and performance of the computer. It helps in quick data retrieval and processing by the CPU.
Data Preserving:
Electricity is required to flow continuously in RAM to preserve the stored information. Once the power is cut, the data is lost, making RAM suitable for temporary storage purposes.
Structure:
RAM is typically in the form of a chip, rectangular in shape, and is physically inserted onto the computer’s motherboard. It integrates seamlessly with the system architecture.
– Cost:
RAM modules are relatively high in cost due to their speed and dynamic nature, making them crucial for the efficient functioning of the computer.
– Chip Size:
The physical size of a RAM chip is larger compared to ROM chips. This larger size accommodates the dynamic nature of RAM, which requires space for quick data access and modification.
Types:
RAM is categorized into two main types: Static RAM (SRAM) and Dynamic RAM (DRAM), each with specific characteristics and use cases.
Elaboration:
Read Only Memory (ROM) is a type of memory that stores data permanently and retains it even when the power supply is cut off.
Accessibility:
ROM is not directly accessible by the processor. Information stored in ROM needs to be transferred to RAM before it can be executed by the processor.
– Working Type:
ROM allows only the reading of information; no changes or updates can be made to the stored data. It holds permanent instructions and data vital for the system’s basic functions.
Storage:
ROM is used for permanent information storage, containing essential instructions and data that are crucial for the computer’s fundamental operations. The data stored in ROM is non-volatile.
Speed:
ROM has a slower access speed compared to RAM. It does not contribute to boosting the processor speed but serves as a stable and reliable source of crucial instructions.
Data Preserving:
Electricity is not needed to continuously flow in ROM to preserve the stored information. Unlike RAM, ROM retains data even when the power supply is cut off.
Structure:
ROM is generally in the form of optical drivers, often made of magnetic tapes. This design ensures stable and long-term storage of essential data.
Cost:
ROMs are comparatively low in cost, reflecting their static nature and role in providing permanent storage for fundamental system instructions.
– Chip Size:
The physical size of a ROM chip is smaller compared to RAM chips. This compact size aligns with the stable and unchanging nature of ROM, which stores data permanently.
Types:
ROM is categorized into three main types: Programmable Read Only Memory (PROM), Erasable Programmable Read Only Memory (EPROM), and Electrically Erasable Programmable Read Only Memory (EEPROM), each catering to specific user requirements and flexibility in programming.
Secondary memory, also known as storage, refers to non-volatile memory external to the computer. It is employed for storing large amounts of data, for permanent or long-term storage of data or programs, and for creating backups.
Secondary storage media can be categorized based on the following criteria:
(i) Retrieval speed: The time taken to locate and retrieve stored data.
(ii) Size/Storage capacity: The ability to store data, with a preference for large storage capacity.
(iii) Cost per bit of capacity: Preference for low cost.
(i) Magnetic Disk: This consists of a Mylar or metallic platter where electronic data are stored. Data are recorded as tiny magnetic spots on its iron oxide coating. Access time is determined by seek time (positioning the read/write head over the paper track) and search time (spinning the required data under the head). Once accessed, data are transferred from the disk to the processor for processing. The transfer rate depends on data density and disk rotational speed.
(a) Fixed disk or Hard disk: Made from materials like aluminum instead of Mylar, it may be permanently installed or in the form of a removable disk.
(b) Floppy Disk: Available in three sizes:
This involves the use of laser beams, highly concentrated beams of light, in the form of:
(a) Optical laser disk, including Compact Disk Recordable (CD-R), Compact Disk Rewriteable (CD-RW), Digital Versatile Disk (DVD), or flash. Data stored can be read by CD-ROM drives, CD-RW drives, DVD-ROM drives, DVD-RW drives, or flash drives.
(b) DVD drive: A Digital Versatile Disk (DVD) is similar to a CD but has a much larger data capacity, consisting of several layers of plastic totaling about 1.2 millimeters thick. DVDs have various types and formats similar to CDs.
These small devices facilitate easy file transportation and usage. Plug-and-play pen drives come in capacities ranging from 16 MB to 1 GB, offering faster and more reliable performance than floppy disks.
The characteristics of different data storage types in the storage hierarchy are summarized below:
Registers:
RAM (Random Access Memory):
SSD (Solid State Drive):
HDD (Hard Disk Drive):
Floppy Disk:
CD/DVD:
Primary Storage Devices:
Secondary Storage Devices
(a) BIT (Binary Digit):
The smallest unit of information represents either 0 or 1.
(b) Nibble:
Four bits make up one nibble.
(c) Byte:
A unit of information consisting of a fixed number of bits, typically 8 bits.
(d) Character:
Represented by one byte; can be a letter, digit, punctuation mark, or special character.
(e) Word:
A combination of 2, 4, or 8 bytes, forming a word.
This information provides a fundamental understanding of memory types, data representation, and data measurement in the context of computing systems.
A fundamental component of digital circuits, a logic gate serves as a foundational building block. Typically featuring two inputs and one output, each terminal exists in a binary state—either low (0) or high (1) at any given moment. The state of a terminal, and consequently the logic gate, may frequently change as the circuit processes data. The logic gate processes input signals in a logical manner, generating an output value of ‘1’ for ON or ‘0’ for OFF based on the input conditions.
There are three primary types of logic gates: AND, OR, and NOT.
Logic gates operate within a binary numbering system, referred to as binary code. This system, consisting solely of 1s and 0s, aligns with the language used by computers.
Logic gates typically have two or more inputs, except for the NOT gate, which has only one input. Regardless of the number of inputs, all gates produce only one output. Inputs and outputs are commonly labeled with letters such as A, B, C, etc.
AND Gate
OPERATION OF THE AND GATE
The AND gate functions akin to having multiple switches in series. For the output to be ‘ON’ (1), all input switches must be closed (ON or set to 1). If any input is ‘OFF’ (0), the output remains ‘OFF’.
TRUTH TABLE FOR “AND” GATE
| INPUT | INPUT | OUTPUT |
|——-|——-|——–|
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
All inputs of the AND gate must be ‘1’ for the output to be ‘1’; otherwise, the output is ‘0’.
OR GATE
The OR gate operates like having multiple switches in parallel. Only one closed switch (ON or set to 1) is needed for the output to be ‘ON’ (1).
LOGIC SYMBOL FOR “OR” GATE
OR Gate
TRUTH TABLE FOR “OR” GATE
| INPUT | INPUT | OUTPUT |
|——-|——-|——–|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
Applying ‘1’ to either or both inputs of the OR gate results in an output of ‘1’; ‘0’ on both inputs yields an output of ‘0’.
NOT GATE
The NOT gate possesses a single input and output, reversing the input signal value. If the input is ‘1’, the output is ‘0’, and if the input is ‘0’, the output is ‘1’.
LOGIC SYMBOL FOR “NOT” GATE
NOT Gate
TRUTH TABLE FOR “NOT” GATE
| INPUT | OUTPUT |
|——-|——–|
| 0 | 1 |
| 1 | 0 |
The NOT gate, also known as an inverter, consistently produces the opposite signal of its input.
In addition to portraying the operations of a logic gate through truth tables and grammatical definitions, logic equations serve as a means to represent not only logic gates and circuits but also, employ theorems and equivalences, to streamline equations by reducing the number of terms. In the realm of logic equations, each Boolean variable is assigned a letter or symbol, akin to the algebraic representation of unknown numerical values using letters—a method referred to as Boolean algebra.
Symbolic logic encompasses values, variables, and operations;
TRUE is denoted as 1,
FALSE as 0.
Variables are represented by letters and can assume values of 0 or 1. Operations function with one or more variables.
The AND gate operation can be expressed through a Boolean algebraic equation. For a 2-input AND gate, the equation is:
[ X = A .B ]
The symbol for the AND gate operation is a centre dot, not implying multiplication. The equation signifies that the output (X) is logic 1 when both A and B inputs are in their 1 states.
The Boolean algebraic expression for an OR gate is given by:
[ X = A + B ]
This equation indicates that the output (X) is logic 1 when either A or B inputs, or both, are in their 1 states.
The NOT gate operation is represented by the Boolean algebraic equation:
[ X = A}
A complement bar is placed over the assigned input letter, denoting that the output state (X) is the opposite of the logic state applied to the input.
Logic gates serve as the foundational components of digital electronics, created through the combination of transistors to perform various digital operations (e.g., Logical OR, AND, NOT). Virtually every digital device, including computers, mobile phones, calculators, and digital watches, incorporates logic gates. To illustrate, consider the single-bit full adder in digital electronics—a logic circuit that executes the logical addition of two single-bit binary numbers.
These are gates that are formed from combination of two logic gates. There are two types of alternative logic gate:
A NAND gate is the combination of an AND gate and NOT gate. It operates the same as an AND gate but the output will be opposite. Remember, the NOT gate does not always have to be the output leg; it could be used to invert an input signal also.
NAND Gate
Notice the circle on output C.
TRUTH TABLE FOR THE “NAND” GATE
INPUT INPUT OUTPUT
A B C
0 0 1
0 1 1
1 0 1
1 1 0
The NAND gate operation can also be expressed by a Boolean algebra equation. For a 2 – input NAND gate, the equation is:
X = A.B
This equation read X equal to A and B NOT, which simply means that the output of the gate is not a logic 1 when A and B inputs are their 1 states.
A NOR gate is the combination of both an OR gate and NOT gate. It operates the same as an OR gate, but the output will be the opposite.
NOR Gate
TRUTH TABLE FOR THE “NOR” GATE
INPUT INPUT OUTPUT
A B C
0 0 1
0 1 0
1 0 0
1 1 0
NOR GATE EQUATION
The NOR gate operation can also be expressed by a Boolean algebra equation. For a 2 – input NAND gate, the equation is:
X = A + B
The expression is the same as the OR gate with an over bar above the entire portion of the equation representing the input. This equation read X equal to A or B NOT, which simply means that the output of the gate is not a logic 1 when A or B are in their 1 states.
Logic gates are in fact the building block of digital electronics, they are formed by the combination of transistors (either BJT or MOSFET) to realise some digital operations like logical OR, NOT, AND etc. Every digital product like computers, mobile phones, calculators, even digital watches contains logical gates.
XOR GATE
The XOR (exclusive – OR) gate acts in the same way as the logical “either or”. The output is “True” if either but not both, of the inputs are “true”. The output is “false” or if both inputs are “true”.
LOGIC SYMBOL FOR “XOR” GATE
XOR Gate
TRUTH TABLE FOR THE “XOR” GATE
INPUT INPUT OUTPUT
A B Y
0 0 0
0 1 1
1 0 1
1 1 0
Comparator is a combinational logic circuit that compares the magnitudes of two binary quantities to determine which one has the greater magnitude. In order word, comparator determines the relationship of two binary quantities. A XOR can be used as basic comparator.
As you can see, the only difference between these two symbols is that the XNOR has a circle on its output to indicate that the output is inverted.
One of the most common uses for XOR gates is to add two binary numbers. For this operation to work, the XOR gate must be used in combination with an AND gate.
XNOR Combination1
To understand how the circuit works, review how binary addition works:
0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 10
If you wanted, you could write the results of
each of the preceding addition statements by
using two binary digits, like this:
0 + 0 = 00
0 + 1 = 01
1 + 0 = 01
1 + 1 = 10
When results are written with two binary digits, as in this example, you can easily see how to use an XOR and an AND circuit in combination to perform binary addition.
If you consider just the first binary digit of each result, you’ll notice that it looks just like the truth table for an AND circuit and that the second digit of each result looks just like the truth table for an XOR gate.
The adder circuit has two outputs. The first is called the Sum, and the second is called the Carry. The Carry output is important when several adders are used together to add binary numbers that are longer than 1 bit.
A computer, a remarkable multi-purpose electronic device, serves as a sophisticated machine capable of receiving instructions in the form of data, processing them with incredible speed, and delivering accurate results. Beyond its seamless execution of tasks, a computer functions as a complex system, comprising two fundamental components: hardware and software.
The hardware of a computer encompasses its physical units or components, forming the backbone of its configuration. This includes tangible elements such as the central processing unit (CPU), memory modules, storage devices, input/output peripherals, and various other interconnected components that collectively enable the computer’s operation.
In contrast, software represents the intangible set of programs processed by the hardware. These programs consist of sequences of instructions that the computer executes to solve specific problems or perform designated tasks. Software plays a pivotal role in dictating the functionality and capabilities of the computer, acting as the bridge between user input and hardware execution.
Delving into the characteristics of a computer, its multifaceted nature becomes apparent:
In essence, a computer stands as a testament to technological innovation, seamlessly blending hardware and software to embody a powerful, efficient, and versatile tool that has revolutionized the way we process information and solve problems in various fields.
Computer hardware refers to the physical components that constitute a computer system. It encompasses tangible elements that are visible and can be touched. The following is an overview of various hardware components:
Computer hardware is broadly categorized into two main divisions:
The system unit houses essential components critical to a computer’s functioning. This includes the central processing unit (CPU), responsible for major processing tasks. The system unit comprises the motherboard, which holds the microprocessor chip, memory chips, expansion slots and cards, buses, and ports.
Peripherals are additional devices connected to a computer to enhance its functionality. These devices serve specific purposes and cannot operate independently. Examples include webcams, printers, and mice. Peripheral devices are further categorized into input and output devices:
Software refers to programs processed by hardware to solve problems or perform tasks. There are two main categories of software:
System software is designed to operate a computer’s hardware and application programs. It acts as an interface between hardware and user applications, including components like BIOS (Basic Input Output System), the BOOT program, and Assembler.
Application software consists of instructions written by vendors to perform specific tasks. Examples include MS Word, Skype, and Explorer. These programs enable users to carry out various functions on the computer.
The origins of computing devices trace back to ancient times when our ancestors utilized primitive methods for counting. Initially, counting was performed using fingers and toes, and when this proved insufficient, early humans introduced pebbles (stones) as a means of tallying their possessions, such as flocks.
Before the advent of more advanced counting methods, our forefathers relied on fingers, toes, stones, and beads for basic arithmetic calculations like addition and subtraction. While effective for small numbers, this manual counting system became impractical for larger values until the invention of the Abacus.
The Abacus, developed around 500 B.C., replaced manual counting methods and was employed in various civilizations, including China, Greece, and Rome. Comprising a rectangular wooden frame with horizontal rods, the Abacus featured beads made of stones arranged on these rods.
Counting with the Abacus involved shifting beads from one position to another, making it a manual device suitable for addition and subtraction. The columns in the Abacus represented different place values, such as ones, tens, hundreds, and so forth. Primarily used for addition and subtraction, the Abacus represented a significant advancement in computational tools.
The slide rule, colloquially known as a slip stick in the United States, emerged as a mechanical analog computer primarily used for multiplication and division. Invented by William Oughtred, the slide rule incorporated a cursor moved along various scales to perform mathematical operations based on logarithmic principles.
While not designed for addition or subtraction, the slide rule found widespread use for functions like roots, logarithms, and trigonometry. Similar to today’s calculators, the slide rule marked a notable advancement in computational technology.
Following the Abacus, Scottish mathematician John Napier introduced Napier’s Bone, a device consisting of rods made of bone specifically designed for multiplication. These rods displayed numbers to facilitate multiplication tables, allowing users to arrange them to represent the numbers involved in a multiplication.
Napier’s Bone served as an early type of calculator, streamlining multiplication calculations with its innovative design.
Blaise Pascal, a French mathematician, invented the Pascal Calculator, also known as Pascaline, in 1642 at the age of 19. This mechanical digital calculator was capable of performing addition and subtraction on whole numbers, featuring interlocking rotating cog wheels with numbers 0 to 9 on the top row of eight movable wheels.
The Pascal Calculator marked a significant milestone as the first of its kind, showcasing the potential of mechanical devices for arithmetic computations.
The Leibnitz Multiplier, invented by German mathematician Gottfried Von Leibniz, was a machine composed of wheels, measuring about 67 cm (26 inches) in length and made of polished brass and steel. Housed in an oak case, it allowed for long multiplication and division through a process involving repeated addition.
The Leibnitz Multiplier represented another leap forward in computational tools, providing an efficient means for complex mathematical operations.
Historical Development of Computing Devices 2: From Pre-Computer Age to the 19th Century
Invented by Joseph Marie Jacquard in 1801, the Jacquard loom revolutionized textile manufacturing, particularly for intricate patterns like brocade and damask. Utilizing punched cards with holes corresponding to design rows, this mechanical loom simplified the production process. Multiple rows of punched holes on each card were strung together to compose the textile design.
Born on December 26, 1791, Charles Babbage, a London banker’s son, proposed a machine capable of 60 calculations per second, laying the foundation for modern computing. Celebrating his 200th birth anniversary on November 1, 1991, scientists and engineers constructed the Difference Engine No. 2 in his honor. Babbage’s analytical engine featured sequential control of arithmetic operations, punched cards for programming, a memory of 1000 words, arithmetic unit, input, and output.
Analytical Engine: Components, Features, and Applications
Charles Babbage’s analytical engine, a pioneering mechanical computer, handled complex calculations, including multiplication and division. Resembling modern computers, it featured a CPU, Mill, and memory called the “store.” The device had a reader for input instructions and a printer to record results on paper, foreshadowing today’s inkjet and laser printers.
Herman Hollerith’s tabulator, used for processing census data, employed electrically operated components to read holes on paper punch cards. Its key components included a pantograph for transferring census information, a card reader, and a sorting table to organize punch card data.
In 1884, William Burroughs created the first experimental model of an adding machine with printed output. Featuring a distinctive high-sloping keyboard, beveled glass front, and a hidden printing mechanism at the rear, the machine focused on additions, lacking provisions for subtraction. Notable components included two large keys for totals and subtotals and three smaller keys for non-additional functions.
In the 20th century, the evolution of computing devices marked significant milestones. During these computer generations, the earliest machines utilized vacuum tubes for circuitry and magnetic drums for memory, occupying entire rooms. These machines were costly, generated substantial heat, often leading to damage.
ENIAC, the Electronic Numeric Integrator and Computer, stands as the world’s first general-purpose electronic digital computer. Invented by John Mauchly and J. Presper Eckert, it employed vacuum tubes for electronic operations.
Features of ENIAC:
Components of ENIAC:
Vacuum tubes, crystal diodes, relays, resistors, capacitors, and hand-soldered joints were integral. Input came from a 1Bm, and output utilized a card punch.
Uses of ENIAC:
ENIAC could perform 5,000 simple addition and subtraction operations.
Electronic Discreet Variable Automatic Computer (EDVAC) was an early electronic computer developed by John Mauchly and J. Presper Eckert.
Features of EDVAC:
Components of EDVAC:
The computer incorporated vacuum tubes, diodes, and consumed 56kw of power.
Uses of EDVAC:
EDVAC was utilized for addition, subtraction, multiplication, programmed division, and automatic checking with ultrasonic serial memory.
Universal Automatic Computer (UNIVAC), the first commercial computer in the U.S., was also created by John Mauchly and J. Presper Eckert.
Features of UNIVAC:
Components of UNIVAC:
Contained tubes, crystal diodes, and relays.
Uses of UNIVAC:
UNIVAC performed arithmetic functions, multiplication, division, and handled various business calculations like payrolls and sales records.
A desktop computer, also known as a PC, is stationary and differs from mobile devices like laptops.
Features of a Personal Computer:
Motherboard, CPU, RAM, power pack, monitor, system software, application software, keyboard, carcass, screen, and mouse.
Components:
Diode, chips, capacitor, resistor, coil, integrated circuit.
Uses:
Word processing, spreadsheet applications, browsing, internet, digital messaging, multimedia playback, computer games, etc.
Laptops, or notebooks, are portable computers designed for mobile use.
Features of Laptop & Notebook Computers:
Webcam, wireless connection, fingerprint recognition, Bluetooth, audio jack, card reader, etc.
Components and Uses:
Similar to desktop components.
Palmtops are handheld portable computers with an operating system compatible with desktops.
Features:
Color screen, expansion slot, wireless capability, voice recorder.
Components and Uses:
Same as those of a laptop, but palmtops are typically powered by off-sheet batteries such as A-cells.
An input device is a piece of computer hardware that is used to send data into the main storage of a computer for processing. Input devices can be classified based on the modality of input (such as mechanical motion, audio, visual, etc.) and whether the input is discrete (e.g., keyboard) or continuous (e.g., mouse’s position).
Modern Input Devices:
Earliest Input Devices:
The keyboard is an input device used to input data into the computer system and is the most common interface between the user and the computer. It is an electronic device with groups of keys electronically linked to the processor when connected to a computer system.
Types of Keyboards:
Standard Keyboard:
Enhanced Keyboard:
Modern input devices explained below:
A camera is an optical input device that captures visual information and converts it into electronic signals. It is commonly used for capturing still images or recording videos. Cameras find extensive applications in photography, video conferencing, security systems, and various multimedia projects.
A compact disc, or CD, is an optical storage medium used for storing digital data. In the context of input devices, CD drives are utilized to read data from CDs, such as software installations, music, or multimedia content. CDs are portable and have been widely used for distributing software and media.
The keyboard is a standard input device with a set of keys, each representing a specific character or function. Users input data by pressing these keys, making it one of the primary means of communication between a user and a computer. Keyboards are crucial for text entry, command execution, and general navigation.
A mouse is a pointing device that allows users to interact with a computer’s graphical user interface. It typically has two buttons and a scroll wheel, enabling users to click, drag, and scroll. Mice are essential for navigating through graphical interfaces, selecting items, and controlling the position of the cursor.
A scanner is a device that converts physical documents or images into digital format. It captures the visual information from a paper or image and transforms it into a digital file that can be stored or edited on a computer. Scanners are commonly used for document digitization and image processing.
A joystick is an input device that consists of a handheld stick and buttons, primarily used for controlling the movement of objects in computer games or simulations. Joysticks provide a tactile and responsive interface, making them popular for flight simulators, racing games, and other applications requiring precise control.
A barcode scanner is a device that reads information from barcodes, which are graphical representations of data in the form of parallel lines. These scanners are commonly used in retail, inventory management, and logistics for quickly and accurately capturing product or item information.
A microphone is an audio input device that converts sound waves into electrical signals. It is widely used for voice input, recording audio, and communication purposes. Microphones play a crucial role in applications such as voice recognition, online meetings, audio recording, and speech-to-text conversion.
Earliest input devices explained below
A punch card, also known as a punched card or perforated card, is an early form of data storage. It consists of a stiff paper card with holes punched through specific locations. Each hole represents a piece of data or a command. Punch cards were widely used in early computing for tasks like data entry, programming, and storing information, with patterns of holes encoding information.
A card reader is a device designed to interpret the information stored on punch cards. It reads the presence or absence of holes in predetermined positions on the card and converts this information into digital data that can be processed by a computer. Card readers were integral components of early data processing systems, playing a key role in handling large volumes of information.
Punched paper tape is another early data storage medium that predates punch cards. It consists of a long strip of paper with holes punched at specific locations. Similar to punch cards, the pattern of holes on the tape encodes data or instructions. Punched paper tape was used for programming, data storage, and communication with early computers and electronic devices.
A magnetic tape unit is a device that utilizes magnetic tape reels for storing and retrieving data. Magnetic tape is coated with a magnetic material, and data is encoded as magnetic patterns on the tape. These units were widely used for data storage and backup in early computing systems. They provided a sequential access method, allowing for the retrieval of data in a linear fashion.
Optical Character Recognition is a technology designed to recognize and convert printed or handwritten text into machine-readable data. In the context of early input devices, OCR systems were developed to interpret characters from printed documents and convert them into digital format. This facilitated the automation of data entry and document processing, saving time and reducing errors.
These earliest input devices played pivotal roles in the early days of computing when manual data entry and processing were predominant. They laid the foundation for subsequent advancements in data storage, retrieval, and input technologies, contributing significantly to the evolution of computing systems.
III. Control Keys – Del, Ctrl, Esc, and Alt: Used in conjunction with other keys to execute specific tasks.
A mouse, like a keyboard, serves as an interface for interacting with a computer screen and is used for drawing and plotting images.
Mouse Categories:
– Clicking: Quickly pressing and releasing a mouse button once.
– Double Clicking: Rapidly pressing and releasing a mouse button twice.
– Dragging: Holding down a mouse button while moving an object.
– Point: Moving the mouse pointer to touch an item.
Mouse Functions:
Mouse Features:
Use your right thumb and the third finger, placing the first finger on the left button and the third finger on the right. Operations may vary between laptops.
A computer output device is responsible for releasing processed data from the computer to either the user or storage devices. These devices produce data in various forms, such as audio, visual, and hard copy. They are peripheral devices connected to a computer via cables or a wireless network.
A monitor, also known as a screen, Visual Display Unit (VDU), Cathode Ray Tube (CRT), or console, is an output device that resembles a TV screen. It is used to view the results of ongoing operations in a computer system.
Data entered into the system becomes visible on the screen, referred to as softcopy. Monitors come in different sizes, such as 12”, 13”, 16”, and 21”, among others.
There are two types of monitors:
Types of Color Monitors include:
Cathode Ray Tube and Flat Panel Monitors
The most common type of monitor for offices and homes is the Cathode Ray Tube (CRT) due to its low cost and precision. Flat Panel Monitors, commonly used by laptops, notebooks, palmtops, and LCD screens, are less bulky.
Various types of computer printers exist, each serving specific purposes:
Additional printer types include:
Printers can also be classified based on whether the printer head strikes the paper. An impact printer strikes the paper, while a non-impact printer does not. Non-impact printers, such as LaserJet and Inkjet printers, tend to be faster due to reduced physical movement during the printing process.
In the realm of printing technologies, two broad categories emerge: non-impact printers and impact printers. Each category encompasses various printing technologies, each with its unique method of transferring ink or toner onto paper. Let’s delve into the distinctions between these two types.
Understanding the distinctions between non-impact and impact printers is crucial for choosing the right technology based on specific printing needs and preferences. Each type offers a unique set of advantages and limitations, catering to a diverse range of printing requirements.
Data refers to raw facts or entities to which no meaning has been attached because they have not been processed. It can include facts about people, places, things, and their activities. When data undergoes manipulation to organize and derive meaning, the outcome is referred to as information.
Data can manifest in various forms, including symbols, alphanumeric characters, alphabets, and numerals. It can be gathered through methods such as counting using counters, observing people, activities, transactions, or events, administering questionnaires, conducting face-to-face interviews, and filling out forms.
Information is defined as any piece of fact, data, or news that is discovered, heard, or communicated verbally, in writing, or through other means.
In market research surveys, completed questionnaires from the public constitute data. After processing and analysis, the resulting report becomes information, which can be utilized for decision-making.
Data refers to raw facts or entities that lack inherent meaning as they have not undergone processing. It serves as the foundational input for information, encompassing details about people, places, things, and their various activities.
Information, on the other hand, is the outcome of processed data, endowed with meaning and relevance for the recipient. When data undergoes manipulation activities, organization, and analysis, it transforms into information that can be comprehended and utilized.
While data is essentially a raw, unprocessed fact, information is the refined, meaningful output derived from the processing of that data.
Data is initially input into computer systems, serving as the raw material that undergoes various operations to generate meaningful information. This process involves the manipulation and organization of data to extract valuable insights and knowledge.
Output from the computer system:
Information, as the processed and refined form of data, is the ultimate output from the computer system. This output is purposeful and tailored to be understandable and useful to the end-user, providing insights and facilitating decision-making.
Meaningless to the user vs. Useful to the user:
Data, in its raw form, may be meaningless to the user without context or processing. However, information, having undergone processing, becomes valuable and useful to the user by providing insights, knowledge, and relevant details.
In essence, the transformation of data into information represents the bridge between raw facts and meaningful insights, facilitating the extraction of knowledge from the vast pool of unprocessed data. This distinction highlights the crucial role of processing and analysis in turning data into a valuable resource for decision-making and understanding.
The keyboard is categorized into five sections:
It is used to:
The mouse, like the keyboard, is an interface for communication with a computer screen. It is used for drawing and plotting images.
Mice are grouped into two types:
Basic Mouse Functions
Point: Moving the mouse pointer to touch an item.
Functions of the Mouse
Features of the Computer Mouse
To use the mouse, you need just two fingers: your right thumb and the third finger. Your first finger should be on the left button, while the third finger should be on the right. These operations may vary from laptop to laptop.