One common type of podium is used to honour medalists in sporting events such as the Olympics. In the Olympics a three level podium is used, the highest level in the centre holds the gold medalist, to their right is a somewhat lower one for the silver medalist. To the left of the gold medalist is an even lower platform for the bronze medalist. Some sports, most notably rowing shun podia, and the symbolism they represent.
Similar podia are used in motorsport, where the first three finishers will usually stand on one at the end of the race to receive trophies. Notable exceptions are the Monaco Grand Prix and the Indianapolis 500 races which have different historic customs. In motor racing, the term is frequently used to refer to a top three placing (as in "he'll get a podium").
TMI.
regardless of size or number, I "really" don't think that any NASCAR or WWF fan is going to think of the term "podia" when his winner climbs on any raised platform at the end of a race ....