The word bit is short for binary digit, which is the smallest unit of information on a computer. A single bit can hold one of two values, which are usually represented by numbers 0 and 1 or literals true and false.

More meaningful information is obtained by combining consecutive bits into larger units. For example, a byte is a unit of information composed of eight consecutive bits.

Using bits, numerical data is represented in binary form. For example, the number 23 is represented in binary as 00010111, which can be represented in a byte as a sequence of eight bits.

Textual data is represented as a sequence of codes, each code represening a single character. A coding standard often used is ASCII (American Standard Code for Information Interchange) which provides codes for 128 characters. For example, the ASCII code for character h is the binary value 01101000 which can be represented in a byte as a sequence of eight bits.