Most floors these days have some kind of urethane finish, but there are a few other types of finish that may be on the floor, especially if it's very old.
One is wax. To test for wax, there are several options (always test in an inconspicuous place, such as in a closet):
Put a little mineral spirits on a white rag and rub it on the floor. If the rag turns yellow/brown, the finish is probably wax. Allow a couple drops of water to sit on the floor. If the finish turns white after about 10 minutes, it's probably wax. Rub a spot on the floor with sandpaper. If the finish balls up, it's likely wax.
In many ways, wax floors require standard maintenance, such as sweeping, vacuuming and wiping up spills immediately. However, wax floors should not be cleaned with a standard wood floor cleaner. When they lose luster in heavy traffic areas, they should be buffed with a polishing brush or pad. White spots from moisture can be rubbed with fine steel wool, a soft cloth or a synthetic pad and a small amount of mineral spirits until the spot is gone. Then the area should be rewaxed and rebuffed.
Another possible finish on an older floor is shellac or varnish. If you scrape a spot on the floor with a hard object such as a coin and the finish flakes off, it is probably shellac or varnish, which can be maintained like a urethane finish.