minuteblue replied: "Refractors are what most people think of when they think of telescopes. They have a lens up front which collects typically dim light over the area of the lens and focuses it to a bright little point near the eyepiece in the back. The eyepiece then magnifies the brightened image so you can see it. Reflectors have a concave parabolic mirror in the back of the tube. These mirrors work as light collectors and are shaped to a slight degree light a satellite dish. The light enters the tube and reflects off the mirror which directs and condenses the light to a secondary mirror, a small flat mirror at an angle, located near the front of the telescope in the middle of the tube. This mirror then directs the light to the eyepiece where again, the now bright little point is magnified so you can see it. In Newtonian and Dobsonian reflectors, the eyepiece is in the side of the tube near the front. Catadioptrics such as Schmidt Cassegrains are also common. These are similar to reflectors but have short tubes and a lens like thing up front called a corrector plate to correct for a problem that arises because they use spherical, and not parabolic mirrors. In most catadioptrics the secondary mirror bounces the light straight back through a hole in the primary mirror and you view through an eyepiece in the back of the telescope. So what's best for star/sky gazing? Well it depends on what it is you want to view. All telescopes have certain imperfections which arise due to the nature of optics. Refractors suffer from chromatic aberration because of the nature of lenses. They don't focus all the color to the same point which can cause color distortions. This can be eliminated by using more than one lens. Such refractors are called apochromatic refractors. These are expensive to make and so they are expensive to buy. In fact they are the most expensive telescopes per inch of aperture, so they are typically small. Because they are small, you would not want to buy one for deep space observing. If you want sharp clear images of bright star clusters, apochromatic refractors are ideal. They will also offer nice views of planets if you can afford a large enough one. If you want to see a lot of galaxies you need a large telescope so it will most likely be a reflector or a catadioptric. A lot of upper end telescopes are catadioptrics called Schmidt Cassegrains. The only optical advantage catadioptrics have to most reflectors is that stars will appear as round points of light in them, not as, well, star shaped stars. They can also be made with super long focal lengths but that's an indepth topic. A large telescope can be used for more than just galaxies. It will give you nice planetary views, nebula views, and just about anything else. For star gazing, that is, looking at large swaths of sky, I really recommend a good pair of binoculars. If you insist on using a telescope for this purpose then you'd want to invest in something called a Rich field, or Richest field telescope. These are reflectors with very wide fields of view. Most of them are hybrids called Schmidt Newtonians."