UCL is written in ANSI C. Both the source code and the compressed data
format are designed to be portable across platforms.

UCL implements a number of algorithms with the following features:

 * Decompression is simple and *very* fast.
 * Requires no memory for decompression.
 * The decompressors can be squeezed into less than 200 bytes of code.
 * Focuses on compression levels for generating pre-compressed data
   which achieve a quite competitive compression ratio.
 * Allows you to dial up extra compression at a speed cost in the
   compressor. The speed of the decompressor is not reduced.
 * Algorithm is thread safe.
 * Algorithm is lossless.

UCL supports in-place decompression.
