Gallery software is software that helps the user publish or share photos, pictures, videos or other digital media. Most galleries are located on Web servers, where users are allowed to register and publish their pictures.
Gallery software usually features automatic image resizing, allows digital media be categorized into sets, and allows comments.
There are several types of gallery software.
Early digital media publishing and sharing was done with imageboards. The boards are by topics, sometimes called "chan". Each discussion in a "chan" are started with a piece of digital media, and follow-up discussions can contain another piece too. Software works in this way: Futallaby, Danbooru.
Triditionally, gallerys are managed. An administrator maintains a set of or hierarchy of albums. The users can upload their digital media in one of the existing albums defined by an administrator, or create their own albums. The users with sufficient permission can re-categorize the digital media others uploaded. Often, the site's administrator can define which album the users are allowed to categorize their media into, or delete other user's content. Examples are opensource galleries Coppermine, Gallery Project.
There are decentralized gallery software that does not have an administrator for managing contents. Pinterest, Flickr and DeviantArt has been successful with this model. Opensource gallery software MediaGoblin works in this way. Each user can create their own "collections", to categorize theirs or other users' media. However users cannot put media into other user's collections. Each user's category is separate. There is no centralized theme or hierarchy for the media.