How quickly they forget...
13th September 2002
.tga is short for Tagra. It is a picture file format that is used to capture screenshots from quake 3 based games. They are much larger then .jpg files which is why it is not used as a standard picture format.
They can be converted by opening them in the following programs and then exporting as .jpgs or .bmps or .gifs or whatever you want:
Paint Shot Pro Adobe Photoshop Macromedia Fireworks
Please post if you have any programs to add to this list.