Package snappy implements the Snappy compression format. It aims for very high speeds and reasonable compression. There are actually two Snappy formats: block and stream. They are related, but different: trying to decompress block-compressed data as a Snappy stream will fail, and vice versa. The block format is the Decode and Encode functions and the stream format is the Reader and Writer types. The block format, the more common case, is used when the complete size (the number of bytes) of the original data is known upfront, at the time compression starts. The stream format, also known as the framing format, is for when that isn't always true. The canonical, C++ implementation is at https://github.com/google/snappy and it only implements the block format.