Dado rail

A dado rail, also known as a chair rail, is a type of moulding fixed horizontally to the wall around the perimeter of a room.
The dado rail is traditionally part of the dado or wainscot and, although the purpose of the dado is mainly aesthetic in modern homes, the dado rail still provides the wall with protection from furniture and other contact. Traditionally, the height of the dado rail is around 36" or 900 mm, which was a suitable height to protect the wall from the backs of chairs. Since the original purpose of the dado treatment is not applicable in modern homes, it is common to see dado rails at 1200 mm or even 1500 mm from the floor.