Editing Desktop search (section)

== Technologies ==
Most desktop search engines build and maintain an [[Index (search engine)|index database]] to improve performance when searching large amounts of [[data]]. Indexing usually takes place when the computer is idle and most search applications can be set to suspend indexing if a portable computer is running on batteries, in order to save power. There are notable exceptions, however: [[Everything (software)|Voidtools' Everything Search Engine]],<ref>{{cite web|title=Everything Search Engine|url=http://www.voidtools.com/|publisher=voidtools|access-date=27 December 2013}}</ref> which performs searches over only file names, not contents, is able to build its index from scratch in just a few seconds. Another exception is Vegnos Desktop Search Engine,<ref>{{cite web|title=Vegnos|url=http://www.vegnos.com|publisher=Vegnos|access-date=27 December 2013}}</ref> which performs searches over filenames and files' contents without building any indices.  An index may also not be up-to-date, when a query is performed. In this case, results returned will not be accurate (that is, a hit may be shown when it is no longer there, and a file may not be shown, when in fact it is a hit). Some products have sought to remedy this disadvantage by building a real-time indexing function into the software. There are disadvantages to not indexing. Namely, the time to complete a query can be significant, and the issued query can also be resource-intensive.

Desktop search tools typically collect three types of information about files:
* file and folder names
* [[metadata]], such as titles, authors, comments in file types such as [[MP3]], [[Portable Document Format|PDF]] and [[JPEG]]
* file content, for the types of documents supported by the tool

Long-term goals for desktop search include the ability to search the [[content-based image retrieval|contents of image files]], sound files and video by context.<ref>{{cite web|url=http://www.niallkennedy.com/blog/archives/2006/10/video-search.html|title=The current state of video search|author=Niall Kennedy|date=17 October 2006|work=Niall Kennedy|access-date=24 June 2015}}</ref><ref>{{cite web|url=http://www.niallkennedy.com/blog/archives/2006/10/audio-search.html|title=The current state of audio search|author=Niall Kennedy|date=15 October 2006|work=Niall Kennedy|access-date=24 June 2015}}</ref>