Bit
From Wikinfo
In computers a bit is the smallest possible piece of information. At a particular location in space (often a memory location) there is kind of energy or there is not. This is a bit. These two possible conditions, energy present or not, are represented on paper as 1 (one) or 0 (zero). True or False is another method to represent the information of a bit.
Computers have the great advantage of collecting groups of bits together and operating on them all at once. For example, pressing a keyboard's key causes 8 bits which together are called a byte. A computer then moves the byte into memory or puts it onto the screen or does other operation with the collection of bits. In the past there have been other quantities of bits which were together called a byte, but today's bytes are normally 8 bits large.
It has become so common to use 8 bit bytes that hard drives and computer memory are sold by the amount of bytes they store, eg. a 100 megabyte (100 million byte) hard drive.
Large collections of bytes (8 bits) and bits (smallest possible unit of information) are called out with the same prefixes. kilo (thousand), mega (million), giga (1,000 million), etc. Abbreviating these terms leads to a potential confusion because both bit and byte are abbreviated with the same letter. The capitol B is used for Byte and a small b for bit. eg. kilobyte (KB), and kilobit (Kb).
Telecommunications or computer network traffic volume is usually described in terms of bits per second. For example, a "56 kbps modem" is capable of transferring data at 56 kilobits, kb, in a single second (which is equal to 7 kilobytes, 7 kB, with capitalised B to mark that we are talking about bytes and not about bits; in case of doubt, b is considered to mean bit); Ethernet transfers data at speeds ranging from 10 megabits per second to 1000 megabits per second (from 1.25 to 125 megabytes per second). The SI prefixes kilo-, mega-, etc., are sometimes modified in meaning when applied to bits and bytes: for an explanation, see Binary prefixes.
For more information see integral data type.
See also: Bitstream, Information entropy, Qubit
A bit is a piece of metal placed in a horse's mouth and connected to reins to direct the animal.
A bit, also called a drill bit is a hardened, sharpened piece, fitted to a rotary drill and is used to drill holes.
Adapted from the Wikipedia article, "Bit" [1], used under the GNU Free Documentation License
