Libraries

Since Windows XP, you've had the option to store your content (documents, videos, pictures, or any other files) in a set of special dedicated folders such as My Documents and My Pictures. These folders are unique for each user, and in Windows Vista they were automatically indexed to provide a superior search experience. But didn't you wish you were able to extend these special folders and include additional folders on your local hard drive or on remote shares? Libraries in Windows 7 allow you to do just that!

With Windows 7 Libraries, you are in control of your data. Using Windows 7 Libraries enables you to manage your own set of folders for various purposes, or add more folders to the My Images library. Libraries are user-defined collections of folders aggregated into a single unified view. By including folders in Libraries, the user is telling Windows (and you the developer) where his important data is located.

Windows 7 Libraries are the users' new entry point for accessing their data. Users will go to Libraries to manage their documents, music, pictures, and other files. And users will expect your application to work with Libraries because they are an integral part of the Windows Shell and play a dominant role within Windows Explorer and other parts of the operating system, such as the Common File dialog.

In some ways, a library is similar to a folder. From a user's point of view, a library looks and behaves just like a regular folder. However, unlike a folder, a library gathers files that are stored in several locations into a unified view. This is a subtle but important difference between a library and a folder. Libraries don't actually store users' items, they only monitor folders that contain items and let users access and arrange these items in different ways. Nonetheless, let's perform a little experiment. Go ahead and launch Notepad and try to save the file to the Documents library. The save operation will complete successfully. However, we just said that libraries are not regular folders that contain files, so what's going on here?