Try before you buy! Here is a list of video editing software programs that give you a free trial first.
However, to fully understand internet video, it pays to know the most common formats. To answer your questions about digital video file formats, I have produced a free, three-minute video tutorial. The video covers all the most common file formats and gives some pros and cons for each.
You often don’t really NEED to know exactly what you’re doing, trial and error gets you to the right place relatively quickly. But if you’re like me, I want to know what’s going on so I don’t waste any time.