How does anim8or work?

http://www.anim8or.com
I saw this program, and it looks very useful for certain things I wanted to do, but I have no clue how to use the program.
Can someone please explain to me how it works?
I saw this program, and it looks very useful for certain things I wanted to do, but I have no clue how to use the program.
Can someone please explain to me how it works?