A lot of people don’t realize that rugs can be layered to give a room more warmth and interest. The most common way to do this is to put an area rug on top of wall-to-wall carpeting. The rug on top adds visual interest and color and grounds the furniture piece or grouping that it is near.
Houzz.com has an article that shows various examples of layering rugs using both traditional persian style rugs and modern rugs, like cow hides. The article also illustrates that if you have an area rug that you love, but it is too small for the specific area, you can layer it on top of a rug that is large enough to cover the area.
The accent area rug adds pizazz to the neutral carpeting or larger solid area rug that it sits on. Area rugs with pattern and color also serve to hide stains, and they can protect the carpet below from wear and damage.