Trending Interior Decorating Styles 2021 - Interior design is defined as, the art or process of designing the interior decoration of a room or building. while a process may include a set of rules or stringent guidelines, the concept of art is much more fluid and subjective. Natural and organic materials strongly decorated to remind us of the exterior life, creating mixed interiors with nature. Interior Decorating Styles 2021 / See which decorating style appeals to you most.