This extension allows the registration for an event based on different participant roles. Right now in CiviCRM, only one participant role is allowed for an event. Say for an instance - you might wanna invite people to host your events, some speakers and rest all would be attendees. In this case you would need an online registration urls to distinctly register them all on the basis of their participnat role. This extension provides the extensibility to do so.
So when you have this extension installed -> go to Manage Events -> Under Info and Settings tab -> at the bottom you would see the following:
You can then give differrent URLs to different people on the basis of their participant role.