A roller coaster is a length of tracks with extreme vertical (and usually lateral) undulation for purposes of giving riders visceral thrills. The structure usually includes an entrance house and platform, to which building attributes may be assigned that are not obviously relevant to a roller coaster.

Roller coasters may be constructed as loops for cyclical routes, or two-ended lengths for rides which go back and forth. The various forms of roller coaster under this category are determined mainly by their plan, irrespective of whether the rider sits or stands or hangs from the track.

The track determines the riders' course through the drops and changes of direction. A chute instead guides free movement within a trough or tunnel without fixed tracks.