Blosc is a high performance compressor optimized for binary data. It has been designed to transmit data to the processor cache faster than the traditional, non-compressed, direct memory fetch approach via a memcpy() OS call. Blosc is the first compressor (that I'm aware of) that is meant not only to reduce the size of large datasets on-disk or in-memory, but also to accelerate memory-bound computations.

It uses the blocking technique to reduce activity on the memory bus as much as possible. In short, this technique works by dividing datasets in blocks that are small enough to fit in caches of modern processors and perform compression / decompression there. It also leverages, if available, SIMD instructions (SSE2) and multi-threading capabilities of CPUs, in order to accelerate the compression / decompression process to a maximum.

Blosc is actually a metacompressor, that meaning that it can use a range of compression libraries for performing the actual compression/decompression. Right now, it comes with integrated support for BloscLZ (the original one), LZ4, LZ4HC, Snappy and Zlib. Blosc comes with full sources for all compressors, so in case it does not find the libraries installed in your system, it will compile from the included sources and they will be integrated into the Blosc library anyway. That means that you can trust in having all supported compressors integrated in Blosc in all supported platforms.