After Effects is a very powerful solution for doing titles and visual effects on digital video, including Chroma Keying (e.g. green screen) and masking.
It also manages to make many great looking effects very easy to implement into your videos. After Effects is extremely powerful, and I found it very easy to use, especially because the help file is so robust. If you want to do anything, it’s so easy just to go into the help file, and look for what it is you want to do. It is also very straight forward, so even without using the help, it is obvious that things like titles, will be in the “Titles” menu. The effects, like chroma key, are also very easy to implement, with straight forward things like drag and drop throughout every element. Of course, because it is so powerful it has rather high system requirements, and can only be run on high end systems. Besides that, it is an essential program for anybody who is serious about doing great effects, or editing digital video. It is definitely worth the high price tag.