Due to the size required to store even compressed medium to high quality video, most formats a consumer will come into contact with use some form of lossy compression. MPEG-1, MPEG-2, MPEG-4 ASP, AVC, VC-1, and many other compressed formats are used for delivery to the consumer, and are also used by consumers to create original content or transcode existing content.
Possibly the biggest obstacle to making use of even the simplest guide is a clear understanding on the meaning of particular settings or instructions. Armed with just a little bit of knowledge about the purpose for what you're doing, you should be able to get better use from a wider array of reference sources.
The Digital Video Fundamentals Series is designed to give an overview of various video topics. This guide explores some basic concepts of lossy video encoding. It's recommended that you be familiar with the basics of digital video terms and concepts, as they'll be used here with little explanation. The rest of our Digital Video Fundamentals series of guides would be a good place to start: