Your avatar can look any way you want it to, up to the limitations of your equipment. If you're ugly, you can make your avatar beautiful. If you've just gotten out of bed, your avatar can still be wearing beautiful clothes and professionally applied makeup. You can look like a gorilla or a dragon or a giant talking penis in the Metaverse. Spend five minutes walking down the street and you will see all of these.
--Neal Stephenson, Snow Crash
One of the primary differences between "real life" and existence within the digital space is the lack of inherent identifying traits in the latter. In cyberspace, one is often only known by one's address, a combination of one's name (or pseudonym) and one's service provider.
One way of remedying this and establishing identity in digital space is through the creation of an avatar, a construct that contains the identifiers that would otherwise be absent. The avatar can either be an approximation of one's own characteristics, or a mask that changes them, in order to communicate or to disguise.