Account

An account is a membership with a multiple-user network, online service, computer, or other service that keeps track of personal information and settings. For example, when you create an account on the Computer Hope forums you can enter information about your computer, keep track of posts, and send private messages to other members.

An account can also be used as an online identity allowing other users to follow what you post/edit/contribute etc, however many sites do have privacy controls that will allow the user to limit how much other users can see.