Guest

An account that enables a user to gain very limited access to a computer. Although some computer operating systems will have a default guest account setup after their installation, many times this account will commonly have to be setup manually by the administrator before it can be accessed.

Unless you plan on having unauthorized users on your computer or network, it is recommended that the guest accounts be disabled on the computer to help prevent potential security issues. This account / username is commonly one of the first accounts a potential hacker may try if he or she is unable to gain access with a higher account.

Also see:  Anonymous, Network definitions