Rtrees - basics of the algorithm

I am trying to understand the basics of RTree algorithm and I am trying to figure out how it performs the search of e.g. all retaurants within 1 km. We would have all objects stores in rectangles in our database, we would then (prbably) build a query rectangle, based on our current position, and then find all rectangles that overlap with it. WOuld we then scan through the results to find the ones of interest i.e. only objects which are restaurants?