I have mentioned that there are mainly 3 types of telescopes. They are refractors, reflectors and catadioptrics. 
I am going to tell what are the advantages and disadvanges of them. I hope you can make up your mind after reading this article. 
By the way, the long contents made up my mind to divide this post into total of 4 episode. Sorry for the inconvenience caused. 
I am going to list out the advantages and disadvantages of refractor now.
Refractor
Advantages
Simplicity of design contributes to ease of use and reliability
Require little or no maintenance
Excellent for lunar, planetary and binary star observing, especially in larger apertures
Good for distant terrestrial viewing
Offer high-contrast images with no secondary mirror or diagonal obstruction
Render good color in achromatic designs and excellent in apochromatic, fluorite and ED designs
Sealed optical tube reduces image-degrading air currents and protects optics
Have permanently mounted and aligned objective lenses
Disadvantages
More expensive per inch of aperture than reflector or catadioptrics designs
Heavier, longer and bulkier than equivalent-aperture reflectors and catadioptrics
Cost and bulk factors limit the maximum practical aperture size
Not very suitable to view small and faint deep-sky objects(DSO) because of the limitations of practical aperture.
Let’s continue the list of reflector tomorrow. 
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