Brown is the color an artist gets by mixing yellow, red, and blue. Chocolate, dark wood, roasted coffee beans, and old-fashioned photographs are all various shades of brown.
You might think of brown as a muddy color, and that's true in a couple of ways: mud is generally brown, and brown paint is a muddy combination of colors. In the category of brown, though, there's endless variety, from toasted bread to rich brown eyes to a horse's light brown mane. As a verb, brown means "to become browner in color" or "to make browner," as when you brown the top of a pie in the oven.