A Codec is a Compressor/Decompressor that allows you to write an animation file to a smaller size that can then be read (without conversion) into a nonlinear editing system. Many designers are confused about WHAT codec to use when rendering from their AE timeline. There are several things to consider when outputting your file.
Always check with the editor or producer who is going to be using the file to find out specifics about the edit system to be used.. Be sure to get version numbers as codecs will often change depending upon which version of the editing software is in place.
Most NLE manufacturers post codecs and render specs on their websites . Look in their support or download section for details,
A detailed and helpful website for information about using After Effects and Avid Editing systems is http://www.wesplate.com. Wes is the creator of Automatic Duck (http://www. automaticduck .com), a helpful utility for moving Avid and Final Cut Pro timelines into After Effects.
When in doubt, use the Lossless setting. This will use the Animation codec, an incredibly high-quality codec that is universal. File sizes will be larger (and you will have to convert upon import or in the timeline) but they file is ˜universal.