Term | Definition |
Hardware | is any physical part of a computer (it is a group of machines) |
Hardware is made up of | (a) The CPU and Main Memory
(b) Input Devices
(c) Output Devices
(d) Storage Devices |
Main Memory | Stores Programmes and data for processing. |
CPU | Controls all operation/jobs, it reads all data into the main memory from an input device; it processes the data according to instructions and produces information using an output device. (So it reads data, changes it and produces information for use). |
Input Device | These Devices read incoming Data and pass it on to the CPU. Examples are: Keyboard, Disk Drive, Scanner, Bar Code Reader, Voice Recognition, and Digital Camera. |
Output Devices | these Accept information from the CPU and display the results for the user. Examples are: Printer, Monitor. |
Storage Devices | these keep information and instructions in the computer so that they can be used again. Examples are: CD’s, Floppy Disks, Hard Drive. |
Mouse | Used to select text, insert text or an icon on a page by clicking and dragging. The cursor changes shape depending on the task E.g. arrow, beam, egg timer shapes. |
Keyboard | Used to type words on the page. The most common type is a QWERTY keyboard; it is laid out in an ‘unfriendly’ manner, in order to slow down speed typists. The most commonly used letters are spaced out to avoid them sticking. |
Bar Code
Reader | They are used in supermarkets where the bar code on the item is scanned and products information is read e.g. its price. |
Wand Reader or Scanner | The wand reader is hand held type that can be used for scanning items e.g. a Library book. |
Point of Scale Terminal | They are used to collect information on a product by scanning the bar code. They record and store information e.g. its price |
Digitiser | Used for drawing illustrations or creating graphics/pictures on a page. |
Camera/Tape Recorder | Used to input voice or visual pictures on to your computer. |
VDE/Voice Data
Entry | It can be accepted human speech and convert it to the spoken word onto your screen. |
OCR/Optical
Character Reader | They are devices that scan the document and turn it into readable form on your screen. It can be text, graphics or photo material. |
MICR/Optical Mark
Recognition/Reader | They are used when documents, contain magnetic digits that contain information |
OMR/Optional Mark
Recognition/Reader | The computer will pick up marks, e.g. pencil marks on a sheet to collect information. E.g. pencil marks on a score sheet |
Touch Screen | It is a special screen which allows you to carry out a task by touching on the screen. E.g. a point of information (POI) |
Light Pen or Stylus | You can use a special pen to touch the ‘touch screen’. It can be used to highlight and select items. |
Monitor/VDU OR Visual Display Unit | This is the screen that you look at; it contains a soft copy of your information.As you ket in text, it appears on the monitor for you to see. |
Flat screen Technology's | Portable computers like laptops, notebooks, and PDA's or personal digital assistants can have high resolution screens. The most common is LCD or Liquid Crystal Display |
Printer | They are used to produce a hard copy of your information. there are many types; the two main types are impact and Non impact. |
Non-Impact Printer | These printers cannot make carbon copies. Examples are: Thermal Printer: they respond to heat and create letters on special paper. |
Impact Printer | They are slower; noiser and often breakdown, they are more expencive |
plotter | They are printing devices that produce a high quality image for drawings |
Audio response | used to provide verbal responses using a voice simulator or pre-recorded messages, e.g. Dierctory assistance. |
Microfiche/film | When large amounts of information need to be stored, miniture copies of documents are kept on microfilm. E.g. Newspapers for the past 100 years. |
Speaker | Send out Audio/Sound |
Digital Projector | Displays the Monitors Image on a Large Screen/Wall |