Both types of telescopes, refractors and reflectors, focus light to a single point. In a refractor, light is BENT as it passes through a lens. In a reflector, light is focused by a parabolic mirror to a single pont. Both types have advantages and disadvantages.
Refractors are durable and largely maintenance free. In addition, they are very efficient in terms of light transmission and in the better grades, provide the best images. An example here would be the Meade 5" AR-5EC, http://www.opticsplanet.com/meade-lxd75 ... scope.html
. On the other hand, refractors (except expensive APO versions) suffer from chromatic abberation (color fringing) and as far as expense goes, are the most expensive per inch of aperture (size).
Reflectors are the best value in terms of cost per inch and are free from chromatic abberation. For the same price as the refractor above, you can get a large Dobsonian reflector such as the Celestron 10" Starhopper, http://www.opticsplanet.com/celestron-s ... scope.html
which is twice the aperture of the refractor above. On the other hand, reflectors are not as durable as refractors - they require periodic collimation (alignment of the mirrors) and cleaning as well.
If viewing planets will be your main use, go with the better images provided by a good refractor. If exploring deep space is your quest, you will need the aperture provided by a large reflector.