Try playing some audio or video files and you'll see only a message complaining that it requires some unknown codec. Which is less than helpful, especially as the error message generally doesn't say what codec the file needs.
SuperEasy Codec Checker can help, though, simply by analysing the clip and telling you about its file format, resolution, bit rate and other details, including any codecs used.
To use the program, click the Add button, then navigate to and select your media file. SuperEasy Codec Checker can open AVI files, MPEGs, MKV, WMV, MP3, OGG, WMA and several other formats (although the program ignored our test MOV files, annoyingly, even though the developer's website says they should be supported).
And in a second or two a tree opens, displaying more information about the file. When we tried a test video, for instance, it displayed the video format, file size, clip duration, video and audio bitrates, video and audio codecs, frame rate, dimensions (in pixels), and more.
None of this is particularly special, and we're not entirely sure why you have to install the program to make it happen: it's simple enough that a portable version should be practical.
Still, if you do find yourself regularly confronted with audio or video files which don't behave as you expect then SuperEasy Codec Checker could be a simple way to find out more.