If you're a user of Windows, there are a few products that Microsoft offers to their users. With the arrival of the new operating system Windows 7, Microsoft has issued several products that will allow storage and the ability to sync files to multiple computers. One of these products is Windows Live Sync.
Windows Live Sync is a free product and download from Microsoft for both Windows and Mac operating systems. It requires a Live or Hotmail email (also free to sign up), which can be attained when on the site. You first need to download the application; after it has installed, sign in with your Hotmail or Live email and password. The first time the application will ask what you would like to sync (videos, documents, music) and then will finish installation. Do the same for any computer you want to sync with; when finish, it will direct you to the Live Sync website.

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From here, you can view devices, as well as add folders and other documents. When a change is made to a file on one computer, it will show up on the other, as log as the computer is online and signed in.
Home Group
Home Group is a new feature for users of Windows 7 and is especially good for homes with more than one computer and who share many documents. Setting up the Home Group is also easy - usually one of the steps when installing 7 - and allows for sharing of documents, folders, pictures, and others that are set up to be shared. As long as a computer is on the home network and has permission, Home Group is available.