Race Levels are levels in which all players race to get to the end of the level first. There are a few main types of race levels, with very different gameplay but all centered around skill-based competition between players.
Original Races are usually built entirely with doors, and have a key at the end to make all the other users fall all the way back to the starting line. Stairs could be considered a type of original race level, although most original race levels are horizontal and have much less uniformity than Stairs Levels.
These levels consist of a wide race track of either solid Blocks or doors with gravity arrows that push players through the track towards the end. Often times, these types of Race Levels will have obstacles that can slow or halt the player that need to be navigated around.
Gameplay in Original Races is made up of players competing to get to the end of the race the fastest. The quickest player will typically give a prize such as a crown, while a key is tripped to send all players back to start a new race. Sometimes races are stacked, and winners are allowed to move on to the next "round". Some levels keep score through the use of Bots.
While a player could technically reach the end without moving themselves, the player would probably not win the race. In order to win a gravity race, the players need to move around, cutting corners and avoiding any obstacles in order to gain a lead over the other players.