Useful Resource - technical glossary

Ever need to know what 1080p vs. 720p really meant? Or 3GPP or M4V? (Don't say no - as journalists these days, we are more likely than even to encounter these tech terms - or have to actually produce in some of them.)

In my wanderings I came across a useful resource, a tech glossary from afterdawn.com. There are some others out there, but this is one of the better ones. Most of the definitions are simplified enough that, even with a few tech-talk spots, you can work your way through them, and the site internally links to lots of other guides.