A Computer essentials

monitor CD/DVD drive

webcam CPU (central processing unit)

software speaker

keyboard printer

mouse modem

B Parts of computer

A computer is an electronic machine that accepts, processes, stores and outputs information. a typical computer consists of two parts: hardware and software. Hardware is any electronic or mechanical part of the computer system that you can see or touch.

Software is a set of instructions, called a program, which tells a computer what to do. There are three basic hardware sections.

1. The CPU is the heart of the computer, a microprocessor chip which processes

data and coordinates the activities of all the other units.

2. The main memory holds the instructions and data which are being processed by

the CPU. It has two main sections: RAM (random access memory) and ROM

(read only memory).

3. Peripherals are the physical units attached to the computer. They include:

Input devices, which let us enter data and commands (e.g. the keyboard and the

mouse).

Output devices, which let us extract the results (e.g. the monitor and the printer).

Storage devices, which are used to store information permanently (e.g. hard disks and DVD-RW drives). Disk drives are used to read and write data on disks. At the back of a computer there are ports into which we can plug external devices (e.g. a scanner, a modem, etc.). They allow communication between the computer and the devices.

C Functions of a PC: input, processing, output, storage

InputWe enter data with a keyboard, a webcam, etc.

Processing The data is manipulated according to program instructions.

Output We can see the result on the screen or in printed form.

Storage We keep data and programs in memory systems where they are

available for processing.

Look at A opposite. Read these quotations and say which computer essential they

Refer to.

1. “Accelerate your digital lifestyle by choosing a Pentium at 4.3 GHz.”

2. “Right-click to display a context-sensitive menu.”

3. “You will see vivid, detailed images on a 17” display.”

4. “This will produce high-quality output, with sharp text and impressive graphics.”

5. “Use it when you want to let the grandparents watch the new baby sleeping.”

6. “Press any key to continue.”

Match the terms with their definitions.

1. CD/DVD drive a. any socket into which a peripheral device may be connected

2. speaker b. device used to produce voice output and play back music.

3. modem c. mechanism that reads and/or writes to optical discs.

4. port d. device that converts data so that it can travel over the Internet.