Buying a computer Part 2.

A: What about things like power and speed, that sort of thing? What do I look for?

B: Well, power depends on speed and capacity - the speed of the processor and the capacity of the memory and the hard disk.

A: The speed of the processor?

B: How fast the computer processes data. Speed is usually given in megahertz or gigahertz. The faster the processor, the more powerful the computer.

A: And capacity?

B: How much storage space there is in the computer. Capacity depends on how much memory there is, how big the hard disk is. You measure RAM and video memory in megabytes. You've also got cache memory. That's in kilobytes. Always look for the highest numbers.

A: What about the hard disk?

B: Hard disk capacity is in gigabytes. Get a big hard disk for multimedia. Audio and video flies use enormous amounts of space. Once again, the higher the numbers, the more powerful the computer.

READ FOR FUN

Read this poem about computer system. It’s not very serious, of course, and you can find a lot of slang words here. Do you understand all of them? Use a dictionary if necessary.

“The system is going to crash"

Scratch the disks, dump the core,

Roll the tapes across the floor,

And the system is going to crash.

Teletypes smashed to bits.

Give the scopes some nasty hits

And the system is going to crash.

And we've also found

When you turn the power down,

You turn the disk readers into trash.

Oh, it's so much fun,

Now the CPU won't run

And the system is going to crash.

Shut it down, pull the plug

Give the core an extra tug

And the system is going to crash.

Memory cards, one and all,

Toss out halfway down the hall

And the system is going to crash.

Just flip one switch

And the lights will cease to twitch

And the tape drives will crumble in a flash.

When the CPU

Can print nothing out but "foo,"

The system is going to crash!

UNIT 4. Bits and bytes

Active vocabulary:	binary system
to stand for	digits
to represent	characters
to avoid	decimal system
to obtain	binary notation
to depend (on)	wires
to generate	switches
to match	condition
to correspond (with)	the current
to be available	refresh buffer
	primary colours

READING

Task 1. With a partner, try to answer these questions.

1 How many digits does a binary system use? What is a 'bit'?

2 What is the difference between binary notation and the decimal system? Give some examples.

3 What is a collection of eight bits called?

4 One kilobyte (IK) equals 1,024 bytes.

Can you work out the value of these units?(kilo-: one thousand) megabyte = ...... bytes/1,024 kilobytes (mega-: one million)

1 gigabyte = ..... bytes/1,024 megabytes (giga-: one thousand million)

5 What does the acronym 'ASCII' stand for? What is the purpose of this code?

Task 2. Now read the text to check your answers or to find the correct answer.