Buying A Telescope

A telescope is an instrument designed for the observation of remote objects. Telescopes that are not used for astronomy can be named transits, spotting scopes, monoculars, binoculars, camera lenses, or spyglasses. Telescopes vary in size, shape and sophistication from homemade spyglasses built from cardboard tubes to arrays of house-sized radio telescopes stretching over many miles. An optical telescope gathers and focuses light mainly from the visible part of the Electromagnetic spectrum (although some work in the infrared and ultraviolet), to make it directly viewing a magnified image, making a photograph, etc.  Professional telescopes often focus the light onto electronic image sensors.
There are three main types of telescope. The refracting telescope which only uses  an arrangement of lenses.  The catadioptric telescope uses a combination of mirrors and lenses.  Radio telescopes which use a directional radio antennae that often have a parabolic shape, for directly viewing a magnified image, making a photograph, etc.  Professional telescopes often focus the light onto electronic image sensors. 
Telescopes which employ two convex lenses cause the image to appear inverted.  Telescopes which are suitable for astronomical use are either good or cheap but not both.  Telescope parts and accessories are a very useful addition to your astronomy experience.  Optical telescopes increase the apparent angular size of distant objects, as well as their apparent brightness. If you are going to purchase a telescope make sure you get the right one for the job you wish it to do. Big Discount on List Prices for Telescopes on Amazon