A CMS (Content Management System) is a software that allows the easy management of the contents of a website. This tool allows to insert, modify, eliminate, decide the graphic aspect of a site, without particular technical knowledge; it can not be used by anyone, but a simple webmaster can create and manage a website without the need of an IT technician.
There are CSMs for all needs, static and dynamic websites, blogs, encyclopedias, forums, etc. that allow you to manage layout, formatting, architecture, sections, change and version management, hierarchy and role privileges, etc…
Through a classic control dashboard therefore, the web designer can administer and manage all aspects of a professional website in complete autonomy.
A good CMS simplifies the use of a website.