The content management systems are the software that enables someone to add, to change, to delete, or to modify the content of a web site. Joomla is one of them.
It is a popular open source content management system that allows you to make your own web site. According to the survey, Joomla is the most popular open source content management system.
The difference of Joomla with other similar software is that it is available for everyone and it is free. It will help you to manage your web site since Joomla will keep the trail of the content posted on your web site.