Vista is designed to handle either of two different kinds of networks: workgroups (small, informal home or small-business networks) and domains (corporate, professionally and centrally administered).

This distinction becomes particularly important when it comes to user accounts.

• A workgroup network. In this smaller kind of network, each computer stores its own security settings, such as user accounts, passwords, and permissions. You can't open files on another computer on the network unless its owner has created an account for you on that computer. Before you can access the files on the Front Desk PC and the Upstairs PC, for example, you must create an account for yourself on each of those machines.

  Clearly, setting up an account on every PC for every employee would get out of hand in a huge company.

  If you're part of a workgroup network (or no network), you'll find that Windows gives you simplified, but less secure, access to user accounts and permissions.

• A domain network. In a corporation, your files may not be sitting right there on your hard drive. They may, in fact, sit on a network servera separate computer dedicated to dishing out files to employees from across the network. As you can probably imagine, protecting all this information is somebody's Job Number One.

  That's why, if your PC is part of a domain, you'll find Windows Vista more reminiscent of Windows 2000, with more business-oriented features and full access to the account-maintenance and permissions-management options. (Only the Business, Enterprise, and Ultimate editions of Vista can speak to domain networks.)