Wall-mounted light fixtures, commonly known as sconces, offer a great way to add character to general room lighting. Replacing an old sconce with a newer, more stylish fixture is a great way to update the look of a room.
If you have ever replaced a ceiling fixture, you will be familiar with the basic technique for replacing a wall sconce. The only real difference is that wall sconces may have special mounting brackets attached to the electrical box to support the weight of the upright light fixture. Replacement will usually mean removing the old bracket and installing a new one included with the new light fixture.
Source: The Spruce