Stack Overflow is optimized for Q & A, while you can do more than just asking questions in a forum (i.e. actually making friends and building communities). The

Stack Overflow is optimized for Q & A, while you can do more than just asking questions in a forum (i.e. actually making friends and building communities). They are both great. Really, every forum should just have a Q & A section that implements Stack Overflow or use a similar widget.