Unlike a mechanical mouse (which uses a ball) or a laser mouse (which uses a laser), an optical mouse uses a reflective LED light in order to track movement, which is why the best mousepads for ...
AFAIK, a "Laser" mouse uses a laser diode instead of a plain LED. what that does for performance isn't something I know.
I've been an optical mouse junkie for a long time now. Sadly, I ran out of replacement microswitches for my Intellimouse Explorer after they started to bounce. Left has been replaced five times, ...