One email address to sign in everywhere
A Microsoft account is an email address and password that you use to sign in to Windows. It's free and easy to set up, and you can do so with any email address you choose, or get a new email address. (For example, you can use an Outlook.com, Gmail, or Yahoo! address for your Microsoft account.)
When you sign in to your PC or device with a Microsoft account, you can get apps from the Windows Store, back up all your important data and files using free cloud storage, and keep all your favorite stuff—devices, photos, friends, games, settings, music, and so on—up to date and in sync.
© 2014 Microsoft