ruby on rails

I'm experimenting with ruby on rails on my system for the first time. the install on my fedora machine went fine, but here's a glitch. I started everyhting up by running ruby script/server. Then I decided to get rid of hte project I first started and follow a tutorial. SO I deleted the directories and went back into the newly created rails project (rails projectname) but when I run ruby script/server from that same directory I get errors. Apparently that port is already in use. How do I stop that?

I suppose I could just try rebooting, but I'd like to know if there's a better way to do it. Perhaps more official? With typing?