The K-Lite Codec Pack is a collection of DirectShow filters, VFW/ACM codecs, and tools. Codecs and DirectShow filters are needed for encoding and decoding audio and video formats. The K-Lite Codec Pack is designed as a user-friendly solution for playing all your audio and movie files. With the K-Lite Codec Pack you should be able to play all the popular audio and video formats and even several less common formats.
The full variant has many additional features. It supports playback of several (lossless) audio formats. It contains VFW/ACM codecs that can be used for encoding. It has playback support for a few legacy audio and video formats. This package is suitable for power users.