How to find file type and file creator on Mac OS X

I have been asked to write an AppleScript that will check a file to see what type it is (Illustrator, Quark, etc), and add the extension related to it if one doesn't already exist. When that's finished and working I'll be sure to post it, but in the meantime I found a helpful utility that allows you to distinguish files by their file creator and file type codes assigned to them. It's called FileType, and is free to download. There are ways to read those file type and file creator codes in the AppleScript to decide what the file actually is, and which program was used to create it. It worked well for what I needed it for, so if you're after something to find the file creator and file type codes on you Mac files, FileType is what I'd recommend