الوحدة الرابعة

Unit: 4

Bits and bytes
Key Words:

Electrical signals – binary notation – grouped – typically – represent
Characters – arrangement – majority – combining – purposes
Reserved – alphabet – symbols – avoid –astronomical – figures
Describe.


Abbreviations:

1. Bit: binary digit.
2. ASCII: American Standard Code for Information Interchange.
3. KB: Kilo Bytes.
4. MB: Mega Bytes.
5. GB: Giga Bytes.

Questions:

1. What is the basic unit of memory?
It is the Bits.

2. Why we use binary notation?
Because it is the only way a computer can
"Understand" any thing

3. What does 1 mean?
1 means on: the current is flowing through the wire.

4. What does 0 mean?
0 means off: the current isn't flowing through the wire.

5. How many different signals ASCII code give us?
There are 256 different signals.

6. How many bytes does ASCII code use to represent characters?
It uses 128 bytes.

7. What makes ASCII system powerful?
Is that these codes are standard.

8. What do the units KB, MB and GB measure?
It measures the RAM memory, the storage capacity of disks and the size of any application or document.

False or true:

1. Information is processed and stored in computers as electrical signals :{ T}.
2. ON means the current isn't flowing through the wire :{ F}.
3. OFF means the current is flowing through the wire :{ F}.
4. ON = 1 and OFF = 0 {T}.
5. Binary notation is the only way a computer can "understand" any thing :{ T}.
6. The ASCII code which has 256 different bytes is powerful simply because it is standard :{ T}.
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