Need help with indentifying a file

HI, i have a file on my pc but i am not sure about its extensions, it says .avi but i don’t think it’s an avi file, i am looking for a program which can identify the file
Answer #1
How big is it? And where’d you download it from?
Answer #2
it is a media file *it’s a movie*
i can only play it with vlc media player and it’s 493 mb
Answer #3
right click the file .. properties .. Type of file : ______ ( the extension )
Answer #4
right click the file .. properties .. Type of file : ______ ( the extension )
+1. BTW, why should you care since you can play the file ?