Using the guest account
Windows 7's guest account lets you give someone access to the computer without having to set up a personal account for them or let them use someone else's account. For example, if visiting friends or family want to use your computer to check e-mail or browse the Web, they can do so with the guest account. The guest account is extremely limited; it can't change most settings, install software or hardware, or even have a password assigned to it (more on passwords in a moment).
No matter how much you trust a visitor, friend, or relative, it is not a good idea to give them access to your user account. If you want them to have fuller access to the computer than what a guest account allows, add a standard account for them. When they no longer need access to the computer, you can delete the account.
Before you can use the guest account, you need to turn it on. To do so, start from the Manage Accounts window and click the guest account's suitcase icon. Then click the Turn On button.