Hello JavaScript Masters!

I'm pretty new to JavaScript, so forgive me, but I'm trying to replace an image with another image onMouseUp...and vice versa. Basically a play/pause button. I like using inline JavaScript, but if that's not possible then I understand.

Since I am trying to learn more about JavaScript, I would welcome guidance on how to achieve this instead of just the code. However, I can usually figure stuff out if I mess with it, so if just posting the code is easier then I can probably still figure out how you did it.

Your Humble Apprentice,

-Bman