A content management system allows you to do the following:
Manage content
Set content management rules
Define content
This means allowing a user to create, publish, edit, and organize content. A good CMS assumes that the user has no technical knowledge. Hence, it provides an easy-to-comprehend user interface for managing content. A flexible CMS will maintain ease of use, even for a novice, and yet give much flexibility to the professional. Publishing the content must extend beyond just displaying the content to designing how the content is shown, making the content accessible and allowing easy search of the content based on various criteria.
These allow the management of content to be delegated and distributed from just one user to many. Different access levels can be granted to different groups and users can belong to any of those defined groups.
Managing content is fine! But what exactly is content? A good CMS allows the end user to define what content is. Content can be anything! It can be raw text, pictures, videos, music, or a combination of a few, or all, of them. A necessity in any CMS is to allow the user to define types of content and give such types a name.