There happens to be a Connect Four game in the section of the hospital where my father stays. So he and I have played quite a few games of Connect Four. I feel kind of bad beating him every time, because he is in there for depression. But I guess not bad enough to let him win.
It is a pretty simple game - somewhere in between tic-tac-toe and checkers. The key, like chess, is the center. If you have the center, then you take away any chance of a horizontal or diagonal win from your opponent. The only way your opponent could win would be vertical. Also, it is important to get three in a row to eliminate moves from your opponent.
The game eventually becomes a game of zugzwang. It doesn't suprise me to learn that "Connect Four on the standard 7x6 board has been solved independently by Victor Allis and James D. Allen. With perfect play, the first player can force a win by starting in the middle column."
When we became bored of the regular way, we would play the game backwards - the first person to make four loses. It is pretty fun that way and really is a game of zugzwang from the beginning.