It's modified baseball without baserunning. There are 3-4 fielders, a pitcher and a batter. The batter gets three outs, and he scores by keeping track of his own hits and runs. A through ball is a single, doubles and triples were subjective, and hitting it past a certain marker (in our case the Banks's lawn) was a home run.

If you're a right-handed batter, only the left side of the field is in play. For left-handed batters, only the right side of the field is in play. Any hit to the opposite side of the field is out.