Interior decoration or décor is the art of decorating a room so that it is attractive, easy to use, and functions well with the existing architecture. The goal of interior decoration is to provide a certain "feel" for the room; it encompasses applying wallpaper, painting walls and other surfaces, choosing furniture and fittings, such as light fixtures, floor plans and providing other decorations for the area such as paintings, sculptures and carpets.

Interior decorating is done professionally by certified interior decorators C.I.D. It is considered a design field. An interior decorator is a very important job.
There is a distinct difference between interior decorating and interior design. Interior decorating is generally focused on the interior items of a space, such as furniture, accessories, finishes, and layout. Interior design, on the other hand, involves manipulating the architectural integrity of the interior space.