1. The Personal Computer. Input devices & accessories.

2. The Personal computer (PC) The PC is a computer that dedicates all its resources to a single user. A computer network can contain PCs and servers. A typical PC consists of a case containing the motherboard and disk drives, a keyboard and mouse for input and a monitor and printer for output.

3. Construction of the PC’s A PC consists of the computer and different peripheral devices i.e. Mouse, keyboard, printers etc.. The case contains the power supply, the motherboard, disk drives and numerous interface cards.

4. Parallel Interface The parallel interface is used mainly for the connection of a printer to a PC It is recognisable as a 25- pin socket. The first parallel interface is called LPT1 the second LPT2, etc...

5. Serial Interface Most computers have two serial interfaces one with a 9-pin and one with a 25-pin plug. A serial mouse is usually connected to the 9-pin serial interface. The 25 pin is available for the connection of a modem etc. COM1 marks the first serial interface, COM2 the second, etc...

6. The Microprocessor The microprocessor is the ‘brain’ of the microcomputer. It is subdivided into a control and data processing unit. The control unit coordinates the entire signal flow in the computer. The data processing unit is the ‘specialist’ for calculations and logical processing.

7. Computer Memory

8. Random Access Memory (RAM) Ram is the abbreviation for Random Access Memory. RAM –storage is volatile storage, i.e. A constant current is required to maintain the storage and therefore the stored information is erased when power is removed. The RAM storage is a read/write storage, because it can be written to as well as read from. It is also called ‘main memory, because it serves as the main intermediary between the CPU and all other storage.

9. Read only Memory (ROM) ROM is the abbreviation of Read Only Memory. ROM storages belong to the non volatile storages i.e. The stored information remains when power is removed. The ROM-storage is read only storage,i.e. information can only be read (comparable with an audio CD or a record) It usually stores parts of the operating system or user-programs.

10. CD ROM and ZIP DRIVE A particular drive is required for the reading of a CD-ROM Storage capacity for a ZIP drive is 250 MB Standard size width = 3.5” (floppy) Standard height 1” high.

11. FLOPPY DRIVE Internal Floppy Disk Drive ideal for computer manufacturers and white box PC manufacturers. This drive stands on nearly 30 years of innovation in disk drive technology.

12. HARD DRIVE The hard drive is your computer’s storage space-it is where you will store all of your data, such as programs and files. A 3 Gb (gigabyte) hard drive or larger is recommended.

13. Flash Drive A small, portable flash memory card that plugs into a computer’s USB port and functions as a portable hard drive with up to 2GB of storage capacity. USB flash drives are touted as being easy-to-use as they are small enough to be carried in a pocket and can plug into any computer with a USB drive. USB flash drives have less storage capacity than an external hard drive, but they are smaller and more durable because they do not contain any internal moving parts. USB flash drives also are called pen drives, key drives or simply USB drives.

14. INPUT DEVICES

15. OUTPUT DEVICES