How do i find out what kind of keylogger i have?

Some high schooler sent me a file and he was a former friend, but he didn't say anythign about the file and I thought it was somethign for real but it was a keylogger. I didnt beleive him but today when i was talking to him on AIM he said i still had it and he said soem of the things it said i did AND IT WAS RIGHT it even ad some of the conversations but only the things i said to the person.