Tracks for a sliding door at a shop
entrance, in Pompeii
, 1st century AD
Some sliding doors are run on a rail, like this one
A modern wardrobe, with sliding doors
A sliding door is a door that opens horizontally, by sliding. Very often, such doors slide along a wall. Sliding doors are commonly used, for example in the bathroom, to separate the shower. They are also used for wardrobes.