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Telescopes: We have been examining telescopes and binoculars. The greatest difference between telescopes and binoculars is flexibility. With the ability to have different focal lengths and interchangeable eyepieces, almost any power of magnification can be achieved.
Brightness: with most binoculars the aperture is around 2 or 3 inches, while telescopes run 2 to 4 or 5 inches upwards to 8 to 30 inch and everything in between. This type of aperture provides ample exit pupil for brightness at higher power.
Resolution: In a perfect world higher magnification shows more detail. The detail you get to see depends a lot on type of scope, glass, mirror grind, eyepiece, and a host of other items. The number one limiting factor for a clear view is the atmosphere your looking through. This is especially true for larger scopes. At higher power with a large scope you will magnify the atmosphere as much as what your trying to look at. The limits of most telescopes is around 50 per inch of aperture So an 8" telescope wont get any better over 400 X magnification. In truth anything over 200 or 300 in power usually shows a fuzzy view unless it is abnormally clear. If you divide the focal length of the scope by the focal length of the eyepiece this will give the magnification of the telescope with that EP. A scope with a FL of 1000 with a 25mm EP will have a mag of 40X. The same EP in a 2000mm scope would be 80x power etc.
There are only a few basic types of telescopes.
Refractors:
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Refractor telescopes are the original telescope. They are the most simple in design and have the least obstructions, therefore they usually give the best view.
The problem with refractors for the average amature astronomer is the cost for the aperture ratio. The cost of objective glass and expert grinding of the lens makes the refractor tough to get much larger than a 7" apertuer and stay cost effective for the general public. More on refractors at My First Scope
Reflectors:
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Reflectors are built with a series of mirrors. the objective end of the scope is typically open with a primary and seconary mirror that directs and focuses the light collected to the focal point at the eyepiece. Reflectors are mostly Newtonian type telescope invented by Sir Isac Newton. Reflectors are the most affordable telescope for the cost to apetuer ratio. They can be used on either a dobsoinan or equitorial mount. More on reflector telescopes at My First Scope.
Catadioptrics:
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Catadioptric is a fancy way of saying combination telescope. They are a combination of a reflector telescope with a corrector lens at the objective, or entrance of the telescope. These are usually the "Schmidt-Casssegrains" or "Maksutov" type scopes depending on which corrector lens is used. Catadioptrics are the most veritile and compact of telescopes. Like the refractor they are sealed, which prevents the air currents in the tube that can disturb viewing in open scopes, plus they require much less cleaning. Most catadioptrics come in the F10 to F15 range with great detail capabillities. Faster cats with a F6 or so ratio require large secondary mirrors which create an obstruction in the view..so you will usually only see these in very large catadioptric scopes or photography lenses. More on Catadioptrics at My First Scope
Rich Field Telescopes:
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Rich field type telescopes are telescopes in the F/4 to F/6 range. These are known as 'fast' telescopes. They offer a very wide field of view (FOV), large exit pupil and work best at low power. These are one of my favorite types of scope. They allow you to see huge areas of the milky way, large globular clusters like M13 and the entire Vail Nebula. They are super for wide field astro photography. RTF can be refractors, or reflectors, newtonian-schmidt reflectors on equatorial or dobsonian mounted. For more on telescopes go to My First Scope
Telescope Binoculars:
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Telescope Binoculars are a combination of telescopes to create huge binoculars. Anywhere from 3 inch to 6 inch refractors up to 24 inch truss tube dobsonians for visual and then there is the LBT that is the equivalent of a 75 foot telescope. See more on telescope binouculars here