Anisotropic filtering in games?

[prakash.gourav]

What is bilinear , trilinear and anisotropic filterings in games??
links will help.

which option must be used for best graphics and which must be be used for fastest performance??

do they need any special hardware like gfx cards?

[nvidia]

which option must be used for best graphics and which must be be used for fastest performance??

Anisotropic filtering will give you the best graphics and bilinear will give you bad looks but better performance..

do they need any special hardware like gfx cards?

Yes

[dheeraj_kumar]

http://en.wikipedia.org/wiki/Texture_filtering

And they do require special hardware.