Bit & Byte

BIT

In computing and telecommunications a bit is a basic unit of information storage and communication (a contraction of "binary digit"). It is the maximum amount of information that can be stored by a device or other physical system that can normally exist in only two distinct states. These states are often interpreted (especially in the storage of numerical data) as the binary digits 0 and 1. They may be interpreted also as logical values, either "true" or "false"; or two settings of a flag or switch, either "on" or "off".

In information theory, "one bit" is typically defined as the uncertainty of a binary random variable that is 0 or 1 with equal probability,^[1] or the information that is gained when the value of such a variable becomes known.^[2]

BYTE

A byte (pronounced /ˈbaɪt/) is a unit of information storage representing the smallest addressable element for a given computer architecture. It often designates a sequence of bits (binary digits) whose length is determined by the architecture. However, the use of a byte to mean eight bits has become ubiquitous.

Prefixes for bit and byte multiples
Decimal Value SI 1000 k kilo 10002 M mega 10003 G giga 10004 T tera 10005 P peta 10006 E exa 10007 Z zetta 10008 Y yotta	Binary Value IEC JEDEC 1024 Ki kibi K kilo 10242 Mi mebi M mega 10243 Gi gibi G giga 10244 Ti tebi 10245 Pi pebi 10246 Ei exbi 10247 Zi zebi 10248 Yi yobi

Source: http://en.wikipedia.org