Vista is the first Windows consumer-oriented operating system to come with a versioning file system. This versioning is called Shadow Copy, although it is exposed to the user as Previous Versions.

Shadow Copy is available in the Ultimate, Business and Enterprise versions of Vista, and is enabled by default on the primary volume. You need to enable it explicitly for external volumes. External volumes include other partitions as well as other hard drives.

Shadow Copy will make a copy of an entire volume, called a Restore Point. You cannot create a Shadow Copy of an individual file. You can though copy and restore individual files.

Incremental changes are stored so minimal disk space is consumed. By default 15% of disk space is used for Shadow Copies.

To access Shadow Copy settings in Vista, open Control Panel and type "restore point" in the search box:

Click on "Create a restore point" to bring up the System Properties dialog:

Here you can create a restore point manually as well as find out more about Previous Versions.

To access previous versions of a file, right click on the file and click the "Previous Versions" tab:

At this point you can open each of the previous versions of the file as well as copy the file or restore it to its original location.

You can also look at previous versions of a folder. When you open that folder in the File versions list you will see something similar to this:

\\localhost\C$\PreviousVersionTest (‎Yesterday, ‎April ‎19, ‎2007, ‏‎4:55 PM)

The path has the date and time the previous version was created. This allows you to look at the entire volume for that restore point.

This can be a very useful feature if you mistakenly delete a file or overwrite something you didn't want to. Realize that the restore points are made once a day and older versions will be overwritten when the Previous Versions storage area fills up.

Previous Versions are also very useful from a forensic point of view. A Forensic Analyst may use previous versions of a file to show inculpatory or exculpatory evidence, showing a timeline of changes to a file.