How do I close a circle without having to deal with tris and ngons? Here's the circle:



I've always been extruding and then scaling the circle inwards. But when I then make a face, there's an ngon. It's not very noticeable, so I've been sticking to that method all the time. But now I am wondering if there's a method that involves only quads. Would that even be possible?
there must be several ways to do it, like the following ones, I'm not sure how it could be useful though. As said by Robin, an easy way to begin is to ctrl F > Grid Fill, then modify the grid that has been created with some alt shift S to make your selection round: