Filters are camera accessories made of glass or plastic disk surrounded by a plastic or metal ring. They can be screwed to in front of your lens and they create different effects on your picture. You can use filters for many diffrent purposes like; protecting your lens, changing the color of the picture or eleminating the glare. There are different types of filters for different purposes;

UV and Protective Filters ;

Uv filters reflects the UV rays back and they are generally used for protecting lenses (which is much more expensive than filters) from knocks and scratches. They do not much effect on your pictures.

Polarizer Filters ;

Polarizer filters are used for eleminating unnecessary reflections from non-metal surfaces like glass and water, also they are great for outdoors photography becouse they increase the intensity of colors and especially skies. However you have to set your shutter time slower (about 2 stops) becouse of the dark glass or plastic when you are using polarizer filter. And there are two general types of polarizing filters; linear and circular. Circular ones can be used on auto focus cameras, linear ones cannot be used with auto focus cameras.

ND (Neutral Density) Filters ;

ND filters simply reduces the amount of light that goes in to your camera. They are good for eleminating overly bright images.