Anti- aliasing smoothens the edges after rendering a shape. It can be done using many algorithms

Anti- aliasing smoothens the edges after rendering a shape. It can be done using many algorithms

4 x (anti-aliasing)

An anti aliasing device uses the technique of minimizing distortion when presenting a high-resolution image at a lower worst quality image. Anti aliasing devices are often used in photography, computer graphics and digital audio among other things.

Because its a shortcut to the advanced settings. Next time, set the Shaders to Low, then switch on the Anti Aliasing. Then apply and go back to the options. You'll see that the AA is back on off, but the advanbce options, Shaders is on High. So it does work.