A pale shade of brown, tan earned its name from the process by which animal hide becomes leather (tanning). The process owes its name to an old German word for oak trees--tannin--that produce an acidic chemical compound used in tanning.
Like other browns, tan evokes warmth and security. It also gives a sense of the same earthy stability that many members of the brown family do.
Tan is considered a neutral, and with its paleness, it can be paired as a complement to almost any other color on the color wheel.