Joomla! is a Content Management System(CMS) software for building websites that dynamically creates each webpage at the time it is requested using the data stored in its database and the files such as images, making Joomla suitable for websites with only one page to an almost infinite number of pages. As a content creator and manager your role is going to require you to understand how to create, update and organise content so that your information you want to share appears in a coherent and structured way to give the most benefit to the viewing audience. You are most likely gong to be using a Joomla website that someone else has already set up and therefore you don't need to be to concerned with the look and feel of the website and other technical aspects at this stage and that lets you focus on building good content on the website.