For sufficiently wide stairs, a rail is mounted to the treads of the stairs. A chair or lifting platform is attached to the rail. A person gets onto the chair or platform and is lifted up or down the stairs by the chair which moves along the rail. Stair lifts are known variously as stair lifts, stair-lifts, chair lifts, stair gliders and by other names.
Straight stairlifts use a straight rail, and the stairlift can only operate in a straight line, with no obstructions at all. Curved stairlifts have rails that follow the path of the staircase and can go around corners.
This type of chair lift should not be confused with the chairlift used by skiers. The term stair climber can refer either to stair lifts, or more commonly to the exercise equipment by the same name.
Now they are seen for use in elderly, fall-prone individuals, and the disabled who are unable to navigate stairs safely