Click to Go BackUnpacked Unit Standard ................................................................................................... Page 70
Unit Standard Title .............................................................................................................. Page 71
117925 Concepts if ICT .............................................................................................. Page 72-136
WHAT IS A COMPUTER?
A computer is a machine that can be programmed to manipulate symbols.Its principal characteristics are:
It responds to a specific set of instructions in a well-defined manner.
It can execute a pre-recorded list of instructions (a program).
It can quickly store and retrieve large amounts of data.
MAINFRAME
A mainframe is a high-performance computer used for large-scale computing purposes that require greater availability and security than a smaller-scale machine can offer. Historically, mainframes have been associated with centralized rather than distributed computing,
Industries using Mainframes
Banking
Banks need to process enormous volumes of transactions. They need to react instantaneously to changes in financial markets. Retail banking revolves around credit card transactions, ATM withdrawals, and online account updates. To fulfill all these needs they depend upon mainframes.
Insurance
The insurance industry depends on mainframes to make sure they can handle the data that drives their business. They live and die on enormous data. Data helps them assess risk, set prices and invest in the right markets.
Healthcare
The healthcare industry also deals with a tremendous amount of data. Mainframes power the secure, compliant, high-volume, and highly available data storage and transactions that make modern healthcare at the top.
Government
Government agencies of all types need to store and analyze vast amounts of data. Mainframes are still helping them to deal with their data.
Aviation
The flight networks are complicated and ever-changing. Airlines and aircraft manufacturers rely on mainframes to help ensure that people and planes arrive where they are supposed to in the most efficient way possible.
Retail
Traditional retailers used the mainframe to help process transactions and keep track of inventories. Online retailers also benefit from the ability of modern mainframe systems to handle enormous volumes of transactions.
MINICOMPUTERS
A minicomputer, a term no longer much used, is a computer of a size intermediate between a microcomputer and a mainframe. Typically, minicomputers have been stand-alone computers (computer systems with attached terminals and other devices) sold to small and mid-size businesses for general business applications and to large enterprises for department-level operations. PERSONAL COMPUTERS
A computer is a device that accepts information (in the form of digitalized data) and manipulates it for some result based on a program or sequence of instructions on how the data is to be processed. A program may be invariable and built into the computer (and called logic circuitry as it is on microprocessors) or different programs may be provided to the computer (loaded into its storage and then started by an administrator or user).
LAPTOP COMPUTERS
A laptop computer, sometimes called a notebook computer by manufacturers, is a battery- or AC-powered personal computer generally smaller than a briefcase that can easily be transported and conveniently used in temporary spaces such as on airplanes, in libraries, temporary offices, and at meetings.
THE PURPOSE OF ICT
-is to describe the components of Information and Communications Technologies
-also describe the hardware components of a pc and software for personal computers.
Computer - is an electronic machine that process data according to instruction
TYPES OF COMPUTERS
- Main frame is a large, powerful computer that can serve a large number of users at the same time.
- Mini computer is a small sized computer that stand alone with attached terminals and other devices.
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- Thin client is a computer with few locally stored programs and depend heavily on network.
- Laptop computer is smaller than a brief case and it can be used in a temporary space .
- Multimedia it is a computer that is optimized for a high multimedia performance.
- PDA is a term of any small mobile hand held that provides computing and information storage.
- Tablet is a wireless, portable personal computer with a touch screen feature.
- Smartphone is a cellular telephone with an intergrated computer and other features not originally associated with the telephone like operating system.
PERIPHERALS
- are devices that can be added to the computer and could be input and output device. TYPE OF PERIPHERALS
- Speaker
- Keyboard and mouse
- Scanner
- Printer
- modem
- Digital Camera
- Microphone
- Plotters
INPUT DEVICE ARE USED TO INPUT INFORMATION
- Keyboard
- mouse
- Scanner
- Microphone
- Digital Camera
OUTPUT DEVICE ARE USED TO DISPLAY/OUTPUT INFORMATION
- Monitor
- Speaker
- Printer INPUT/OUTPUT DEVICES ARE DEVICES THAT FIT UNDER BOTH.
- CD Rom
- Flash drive
- Touchscreen
- Modem
- Floppy disk PORTS IS A PHYSICAL DOCKING POINT USING WHICH AN EXTERNAL DEVICE CAN BE CONNECT TO THE COMPUTER
TYPES OF PORTS
- VGA port is for Visual/Video
- Power connector is a Three pronged plug used to connect power cable.
- Serial port is used for external modems and older computer mouse.
- Parallel port is used to connect printers and scanners
- USB port is used to connect is used to connect all USB external devices.
- PS/2 is used for older computer mouse and keyboard
- Modem port is used to connect network cable.
- Game port is used to connect joystick to a pc
- Sockets connects microphones, speaker and earphones.
HARDWARE
- is a physical part of the computer that you can see and touch.
HARDWARE COMPONENTS
-Motherboard is a set of a computer hardware components arranged so that they are physically connected.
- CPU it manages all the computer operations.
- RAM makes the space available for your computer to read and write data to be accessed by CPU.
- ROM contains data that cannot be modified and hence retain it even when the computer is switched off.
- Modem is an electronic device that enables a computer to communicate with other computers over a network.
- Sound card enables the computer to produce sound to be broadcasted through the speakers.
- Graphic card enables the computer to transform data into pictures to be displayed on the monitor.
- Input devices are used to enter data into the computer and also instruct it what to do.
- Output devices their function is to transform all output information into text, animated, sound and static images.
SOFTWARE
- it’s the information that computer uses to get the job done.
TYPES OF SOFTWARE
* OPERATING SYSTEM SOFTWARE - is a software that communicates with the hardware and allows other programs to run, also controls the overall activity of the computer.
* APPLICATION SOFTWARE - lets you accomplish tasks, such as writing a letter, or adding a column of figures, so it’s the software that do your work. Examples of applications are word processing, spreadsheet and presentation.
COMPUTER NETWORK * INFORMATION NETWORK - is a set of two or more computers connected together to share information and resources like printer and hard disk.
* DATA COMMUNICATION
- is the transmission of electronic data over some media.
* TELECOMMUNICTAION
- is a process of transferring information over a distance through radio waves and optical signals.
THE USES OF COMPUTER NETWORK
- Network are used to access shared data
- Networks are used to send email with attachments
- Network are used to communicate globally
THE BENEFITS OF COMPUTER NETWORK
*HELPS TO ENHANCE CONNECTIVITY
- Network connect and link unlimited number of computers.
* NETWORKING HELPS IN SHARING OF HARDWARE
- Network helps in sharing of different kinds of hardware for example sharing a single printer in an office of twenty people is done through networking of wires.
* INTERNET
- The beautiful gift of networking Is that internet is massively used by people all over the world
* DATA SHARING
- sharing data through the network helps save a lot of time and energy
* NETWORKING HAS PROMOTED GAMING
- many game players are playing games all over the world using the common servers.
LAN (LOCAL AREA NETWORK)
- supplies networking capability to a group of computers in close proximity to each other such as an office business, school or at home.
ADSL (ASYNNETRIC DIGITAL SUBSCRIBER LINE)
- IS an internet connectivity technology that within South Africa enables an ordinary telephone line to reach speeds of up to 490kbps.
TYPES OF STORAGE DEVICES
- Hard dive
- Floppy disk drive
- Zip drives
- Tape streamer
- Flash drive
- Cd- Rom drive
- Cd
- USB
HARDWARE MAINTANANCE
The electronic parts of a computer should always be treated with care. Do not
- Remove the cover of the computer
- Remove the hardware parts
- Drop the computer, as the electronic hardware inside is very sensitive and may sustain damage
- Spill liquids on the hardware
- Drop or throw the mouse or keyboard around
Always
- keep the computer and other hardware components in a cool dry place
- Remove the cd rom from the cd rom drive
- close the cd rom drive after use
- remove the stiffy from the stiffy drive
THE FLOW OF INFORMATION INTO A PC
- Rom is responsible for the startup sequence of the pc. The startup sequence ends when windows appear on the monitor.
DEFINATIONS
* OPERATING SYSTEM
- Is a software that communicates with the hardware and allows other programs to run.
* PROGRAMS
- Is an executable software that runs on a computer.
* APPLICATIONS
- Is a software that runs on your computer.
* NETWORK
- two or more computers connected to each other.
