Virtual folder

In computing, a virtual folder generally denotes an organizing principle for files that is not dependent on location in a hierarchical directory tree.

Virtual folders provide a means for making it easier for users to find files that are content-related, such as by project.

The initial developer preview of the operating system, released in October 1995, included database-like functionality to make it easier for users to manage their files.

If a user wanted a query to stay around longer, they could uncheck a "Temporary" flag in the Find dialog.

[6] There are many variants of the Smart Folder concept that can be seen in applications that use the Spotlight engine, usually identified by a gear symbol on a purple-hued icon.

[12][13] By default, Windows Vista references the disk partition and user profile of a created Saved Search as part of its scope, which inhibits their ability to return content from different machines or partitions when transferred to other machines.

Microsoft released a SearchMelt Creator utility that changes the scope of Saved Searches to reference the %USERPROFILE% environment variable, which allows them to operate on other machines or profiles; users can also edit Saved Searches manually to reference %USERPROFILE% to facilitate sharing.

[14] Saved Searches additionally allow users to create stacks of data, which are collections of items assembled by properties such as document authors.

[12][18][19] Stacks in Saved Searches in pre-release builds of Windows Vista could also be created by users, or write properties to data by drag-and-drop — in a feature known as metadata painting, dragging a document onto an author stack, for example, would assign that author to the document.

Libraries have a shell namespace extension in Explorer and their XML files can be reused across Windows installations or the network.

In early 1991, the Emacs-based mail reader VM provided a virtual folder facility in its version 5.09.

[25][26] The Opera web browser released a new mail client (beta in November 2002, final version in Jan 2003), M2 in which virtual folders (called access points) were used for all email management.

Virtual folders were automatically made for active contacts, for attachments and for assigned labels.

Gmail, first released in 2004, bases all of its mail management on virtual folders accessed via labels.

[27] In July 2002, Apple announced version 3 of iTunes which includes Smart Playlists which can be considered a variant of a virtual folder.

[clarification needed] The only difference is that the search executed on accessing them is not on the file system's folder hierarchy, but on their internal data-store.