Stair lifts are devices which are used to support lifting of equipments like a car, a wheelchair etc, over stairs. They can either be inbuilt, or can be installed on use as well. These devices help in easy going of things, and making work simpler, rather than people lifting the things or persons on their own over the stairs. They may be rails mounted on the stairs so as to make room for the normal stair walk, or it may some portion constructed in the stair itself, which is a whole straight way through the stairs.
Either ways can be used depending upon your need and the frequency of use. A rail type stair lift comes with a pair or rails and carriage. The rails are either permanently installed, or are foldable as well. If you frequently use the stair lift, then a permanent one will work fine. A permanent type of stair lift also works if your stairs are wide enough to bear the room for it, and also for normal movement. There is a carriage to hold the things put over it, and slides over the rail through the stairs to the place where it needs to be taken. For all other types, a foldable one is good and portable.