This section discusses the concept of domains and trusted domains. A domain is a group of Microsoft Windows NT Server computers (and LAN Manager 2.x servers) that work together to form a single security image. The user and group accounts within the domain is handled as a single entity. The concept was initially introduced with LAN Manager and has been carried forward into Microsoft Windows NT. Trusted domains are a new concept added to domains. Microsoft Windows NT Server has the ability to link domains to create even larger user and group structures for large enterprise deployments.