Short Answer

Brown diamonds are one of many 'shades' of colored diamonds. Other colored diamonds, also called "fancy diamonds," include pink, yellow, blue, green, purple, black, red and orange.

Some brown diamonds can be referred as chocolate diamonds, based on the intensity of their colour.

Longer Answer

Although colored diamonds were once considered undesirable, they have become very popular amongst those looking for an alternative to conventional white diamonds.

Some colored diamonds gained commercial names over the years thus having multiple names which actually mean (more or less) the same thing.

For example: yellow diamonds are also known as Canary Diamonds (even though usually canary diamonds describe a diamond of a pure, strong yellow color). Some brown diamonds are described as chocolate diamonds.

NB: The words Chocolate Diamonds is a wordmark owned by Le Vian Corporation as a registered trademark. This wordmark covers "Jewelry, watches, timepieces, jewelry watches, jewelry chains, jewelry pins, jewelry amulets and jewelry rings all made in whole or in part of diamonds."