User Account is a type of account assigned to an individual user to allow that user to access network resources. These resources can include folders containing files, shared printers, mail services, or databases. The network administrator grants a user access to these resources by assigning the user a user account.
Two types of user accounts are available in Microsoft Windows NT and Windows 2000:
A group account acts as a container for grouping user accounts. Group accounts simplify network administration by allowing multiple users to be granted or denied access to network resources in a single step - by granting or denying access for the group account to the resource.