Question about software.

Hello,
If I am dealing with a programmer (Elance) on developing some software exactly who has the copyright? Is this something that needs to be settled before a deal is made? I have seen programmers on software forums offering to sell the software someone has just paid them to write so I am curious as to how that works. Seems kind of unethical to me but maybe I am wrong.

It's a small piece of software just to get my feet wet but I have never dealt with this before. I am learning PHP/MYSQL so this experience well also help if I begin to write scripts for others. Thanks.

Scott S.