can we send output through mail

Hi gurus,

I would like to know that can we send a billing document through mail or not. If yes how can we send what would my out type is the same thing like rd00 or some thing else like mail out put type. What is the program for this and what is the form for sending these a customer i means bill to party.

Thanks in advance. Points willlbe rewarded.

Thanks & Regards

Expecting helpful and valuable answers.