This type of telescope is pretty much summed up in the name. The image is brought to the eye through a series of reflective mirrors. Although there are several types of reflectors including some exotic "off-axis" reflectors, the most common type is the Newtonian reflector. The key element of a Newtonian reflector is either a spherical or parabolic mirror at the bottom of the telescope which is referred to as the "primary" mirror. In a Newtonian design this is the first of two mirrors that intercept the incoming light. This mirror directs the light toward a tilted flat mirror appropriately called the "secondary" which deflects the light through a focuser to an eyepiece. All of the telescopes in the "Reflectors" section are Newtonian reflectors.
Reflector telescopes are generally the best value in terms of cost per inch of diameter, or aperture. The range in cost and quality runs from a small diameter long instrument with a spherically shaped primary (for example 3" in diameter and 30" long) to a gigantic "light bucket" with a short focal length parabolic primary (20" or more in diameter and perhaps 8 or 9 feet long).