How do I get out of bash and xterm on linux?

[greenpearl92]

I am in a Java Programming class and we work in a Linux environment. We were exploring files and such when I did something I did not remember with like I think a file named bash. I logged out of my account that day and left everything as it is. The next day, my normal terminal called term became xterm and my normal username ........ became bash3.2$. I did not know how to get out of it and it is making my life hard. So how do I exit out of this crap with linux commands on terminal? Instructions would be appreciated! Thanks!