If you've ever listened to a recording of yourself and thought you sound completely different, you're not alone. But more than that, you were also correct. Here's why it sounds different.
You see, when you speak, you hear your voice as other people do, but you also hear a contribution which comes from vibrations passing through your skull. In this video, Greg Foot explains how that changes what you hear—and why, sadly, the recording of your voice is actually how you sound to everyone but you. [YouTube]