Basic Programming - Atari 2600

I don't have any experience with Basic Programming, but I'd say it's as you describe — a way for beginners to try the basics of programming.
Andrew Davie gives a very good explanation of how professional programs for the Atari 2600 were made here:
http://www.randomterrain.com/atari-2600-memories-tutorial-andrew-davie-01.html
The page is in English, but everything is explained really well.

Could you actually do anything useful with it, or was it more of a fun way for beginners to try programming? I'd be quite interested to know what tools and methods were used to develop games for the Atari 2600.