Lempel–Ziv–Welch (
LZW) is a universal
lossless data compression algorithm created by
Abraham Lempel,
Jacob Ziv, and
Terry Welch. It was published by Welch in 1984 as an improved implementation of the
LZ78 algorithm published by Lempel and Ziv in 1978. The algorithm is simple to implement, and has the potential for very high throughput in hardware implementations. It is the algorithm of the widely used
Unix file compression utility
compress, and is used in the
GIF image format.