A content management system (CMS) is a computer application used to create, edit, manage, search and publish various kinds of digital media and electronic text. CMSs are frequently used for storing, controlling, versioning, and publishing industry-specific documentation such as news articles, operators’ manuals, technical manuals, sales guides, and marketing brochures. The content managed may include computer files, image media, audio files, video files, electronic documents, and Web content.
A CMS may support the following features:
* identification of all key users and their content management roles;
* the ability to assign roles and responsibilities to different content categories or types;
* definition of workflow tasks for collaborative creation, often coupled with event messaging so that content managers are alerted to changes in content (For example, a content creator submits a story, which is published only after the copy editor revises it and the editor-in-chief approves it.);
* the ability to track and manage multiple versions of a single instance of content;
* the ability to capture content (e.g. scanning);
* the ability to publish the content to a repository to support access to the content (Increasingly, the repository is an inherent part of the system, and incorporates enterprise search and retrieval.);
* separation of content’s semantic layer from its layout (For example, the CMS may automatically set the color, fonts, or emphasis of text.).
Enterprise content management (ECM) is a set of technologies used to capture, store, preserve and deliver content and documents related to organizational processes. ECM tools and strategies allow the management of an organization’s unstructured information, wherever that information exists. 
The “official” definition of enterprise content management was created by AIIM (Association for Information and Image Management) International, the worldwide association for enterprise content management in the year 2000. The abbreviation ECM has been reinterpreted and redefined many times .
In autumn 2005 AIIM defined ECM as follows:
Enterprise Content Management is the technologies used to Capture, Manage, Store, Preserve, and Deliver content and documents related to organizational processes.
In winter 2006 AIIM added the following paragraph to the definition:
ECM tools and strategies allow the management of an organization’s unstructured information, wherever that information exists.
This new term is intended to completely encompass the legacy problem domains that have traditionally been addressed by records management and document management. It also includes all of the additional problems involved in converting to and from digital content, to and from the traditional media of those problem domains (such as physical and computerized filing and retrieval systems, often involving paper and microforms). Finally ECM is a new problem domain in its own right, as it has employed the technologies and strategies of (digital) content management to address business process issues, such as records and auditing, knowledge sharing, personalization and standardization of content, and so on.