That was a big joke in the Jetsons though. His day was literally sitting at a desk poking a button and he was apparently bad enough at it that his boss was constantly up his ass about it.
It's a tracking code Google assigned to you and stuffed into your links even though it's useless to you. What it does is tell Google who clicks on your links so they know who you're talking to on other websites. It's the part after ?si=