concrete5 is an open source content management system (CMS) for publishing content on the World Wide Web and intranets.
Concrete5 was designed for ease of use, for users with a minimum of technical skills. It enables users to edit site content directly from the page. It provides version management for every page, similar to wiki software, another type of web site development software. concrete5 allows users to edit images through an embedded editor on the page.
Concrete5 code is based on Model-View-Controller architecture and object-oriented programming. Some core features are: integrated server caching, developer API, version tracking system and search engine optimization.
Concrete5 features in-context editing (the ability to edit website content directly on the page, rather than in an administrative interface or using web editor software). Editable areas are defined in concrete5 templates which allow editors to insert blocks of content. These can contain simple content (text and images) or have more complex functionality, for example image slideshows, comments systems, lists of files, and maps. Other add-ons can be installed from the concrete5 Marketplace to extend the range of blocks available for insertion. Websites running concrete5 can be connected to the concrete5 website, allowing automatic upgrading of the core software and of any add-ons downloaded or purchased from the Marketplace.