In order to obtain an account on any central system you must first contact your Group Administrator who will register you on the necessary systems once you have read the Computer Rules and signed the registration form. This form must then be sent or taken to the UCO in building 513 where your account(s) will be validated. For UNIX accounts a User Identification Number (UID) will be given. This is a unique number that is given to your account-name and should be valid over all the centrally-maintained UNIX-type platforms at CERN. Even for those who have private workstations only, it is advisable to see your Group Administrator and be granted a UID number, even without being registered on the central services, so that this number is reserved for your use.