computer science from 1
Chapter 3: Computer System
How is information represented in the computer?Bits and Bytes
Computers understand only the language of electricity, ON or OFF. That is why the binary number system is used, This system is based on two numbers or digits 1 (for ON) and o (for OFF). Each number is called a binary digit or bit for short.
Bit: A bit is the basic unit of data recognized by the computer.
Byte: A byte is a group of bits that is large enough to represent many symbols (& concepts) that can be manipulated by the computer.
Thus all our human communication symbols have to be converted into a code of 1s and 0s for processing and storage by computers and then converted back again to human communication symbols at the output for us to understand.
Some computer capacity expressions;
|
Unit |
Capacity (SI unit) (Approximate) |
Capacity (IEC units) |
|
Bytes |
|
A byte is 8 |
|
Kilobyte Kb |
1000 (103) bytes |
1024 (210) bytes |
|
Megabyte Mb |
1 000 (103) kilobytes |
1048576 (210) bytes |
|
Gigabyte Gb |
1 000 (103) megabytes |
1073741824(230) bytes |
|
Terabyte Tb |
1 000 (103) gigabytes |
1099511677776(240) bytes |
File Formats
A file format is a standard way that information is encoded for storage in computer file. It specifies how bits are used to encode information in a digit storage medium. File formats may be proprietary or free and maybe either unpublished or open.
par Claude Foumtum