User-generated content (UGC), also known as Consumer generated media (CGM) or user-created content (UCC), refers to various kinds of media content, publicly available, that are produced by end-users.

The term user generated content entered mainstream usage during 2005 having arisen in web publishing and new media content production circles. Its use for a wide range of applications including problem processing, news, gossip and research reflects the expansion of media production through new technologies that are accessible and affordable to the general public. All digital media technologies are included, such as question-answer databases, digital video, blogging, podcasting, mobile phone photography and wikis. In addition to these technologies, user generated content may also employ a combination of open source, free software, and flexible licensing or related agreements to further reduce the barriers to collaboration, skill-building and discovery.

Sometimes UGC can constitute only a portion of a website. For example on Amazon.com the majority of content is prepared by administrators, but numerous user reviews of the products being sold are submitted by regular visitors to the site.

Often UGC is partially or totally monitored by website administrators to avoid offensive content or language, copyright infringement issues, or simply to determine if the content posted is relevant to the site's general theme.

However there has often been little or no charge for uploading user generated content. As a result the world's data centers are now replete with exabytes of UGC that in addition to creating a corporate asset may also contain data that can be regarded as a liability.