The smallest unit of digital information. A single bit can carry just one of two values: 0 or 1. There are eight bits in a byte, 1,024 bytes in a kilobyte, 1,024 kilobytes in a megabyte and 1,024 megabytes in a gigabyte. Sometimes, though, the traditional 1,000 is used rather than 1,024, leading to confusion. A bit should generally be abbreviated as lower-case 'b' (compared to 'B' for byte). Thus 128kb/s means 128 kilobits per second, whereas 128kB means 128 kilobytes.