Interior decoration is the discipline or practice of designing interior or indoor spaces ranging from residential to commercial buildings. It could be as simple and easy as designing study storage to as complex and elaborate as designing a 3-storey Edwardian era home.  Interior design especially contemporary ones are mainly utilized to provide aesthetics, practicality, functionality and sustainability to the house or building. However, there are also things what this discipline is not. For instance, a good interior design is never elitist, never overpriced or too expensive. It must not also be extremely upscale or high end and upper class. You could have simple, inexpensive and still functional design concepts for your home interior that work!