Conversions snippets are extensions of Conversion class with snippets. Most simple conversions will be done with built-in templates or with little modification. That was designed to simplify typical conversions and teach how to create own solutions.
FFmpeg.Conversions.FromSnippet is a good point to start using Xabe.FFmpeg library. Every method may be used as template for a more conversions. If you think that your new conversion method is really useful, do not hesitate about include them to Xabe.FFmpeg.FFmpeg.Conversions.FromSnippet by pull request.
Every method is only a snippet and uses only IConversion with specific configuration. See the source to know how chosen conversion works.