DAZ Studio is built with the intention of serving every level of user, ranging from beginner to seasoned veteran. This is accomplished by simplifying user experience, while adding features and tools with each new configuration of the application. We call each of these configurations an edition.
Not all editions are created equal. The higher the edition, the more features you will have available to you. You will also have greater control over customizing the User Interface (UI) to better suite your workflow. However, as with many things, the ability to do more with DAZ Studio comes with a responsibility to know more about the tool.
Below are links to the product pages, on the DAZ 3D site: