K-Lite Codec Pack
is a collection of codecs and related tools. Codec is short for Compressor-Decompressor. Codecs are needed for encoding and decoding (playing) audio and video. This Codec Pack is designed as a user-friendly solution for playing all your movie files. You should be able to play all the popular movie formats and even some rare formats.
There are five variants of the K-Lite Codec Pack:
The basic variant contains everything you need to play all the common video file formats. Such as AVI, MKV, MP4, OGM, and FLV. This pack is for those who like a small no-nonsense pack.
The standard variant contains some additional features compared to the basic variant. It contains Media Player Classic, which is an excellent player for video files. It also has (better) support for playback of DVDs. This pack is recommended for the average user.
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.
The corporate variant is a special version for use in a corporate environment. It is similar to the full variant, minus a few items, but almost just as powerful. It has a strong focus on open source software.
The mega variant has almost the same contents as the full variant, but additionally contains Real Alternative and some extra VFW/ACM codecs.