What Is a Bit in Computer Networking?

Computer Technology Is Based on the Concept of the Bit

A binary digit, or bit, is the most basic and smallest unit of data in computing. A bit represents one of two binary values, either a "0" or a "1." These values can also represent logic values like "on" or "off" and "true" or "false." The unit of a bit can be represented by a lowercase b. 

In networking, bits can be encoded using electrical signals and pulses of light and be transferred through a computer network.

Some network protocols send and receive data in the form of bit sequences. These are called bit-oriented protocols. Examples of bit-oriented protocols include point-to-point protocol (PPP).

Bits and Bytes

A byte is made up of 8 bits in a sequence. You are probably familiar with a byte as a measure of file size or the amount of RAM in a computer, for example. A byte can represent a letter, a number or a symbol, or other information a computer or program can use.

Bytes are represented by an uppercase B.

Uses of Bits

Though sometimes written in decimal or byte form, network addresses like IP addresses and MAC addresses are ultimately represented as bits in network communications.

The color depth in display graphics is often measured in terms of bits. For example, monochrome images are one-bit images, while 8-bit images can represent 256 colors, or gradients in grayscale. True color graphics are presented in 24-bit and 32-bit graphics.

Finally, special digital numbers called "keys" are often used to encrypt data on computer networks. The length of these keys is expressed in terms of the number of bits. The greater the number of bits, the relatively more effective that key is in protecting data. In wireless network security, for example, 40-bit WEP keys proved to be relatively insecure but the 128-bit or larger WEP keys used today are much more effective.