system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:FXAA, SMAA, and other anti-aliasing options

OK, so i know what anti-aliasing is. But what does it mean by '8xAA' or 'SMAA' or all those other options?
gpt
There are 2 main kinds of AA.

The first uses sampling (which is why it's called SAA), which basically means that it calculates what colors the pixels would be if you were at a higher resolution, and then averages them to find the color the actual pixel should be. The edges are technically still jagged, but it's harder to tell because the color is blended. The number is how many extra pixels are being calculated before averaging them out. 8xMSAA means each pixel on an edge is broken down into 8 pixels, those colors are calculated, and then averaged back into the pixel you actually see.  
There are different kinds of SAA which do this in different ways (FSAA and SSAA do this for every pixel on the screen while MSAA only does it for edge pixels, which takes less processing power but sometimes misses things).

The other type of AA is a type of post-processing (effects added after the image is actually created, but before it's displayed on the screen). MLAA and FXAA do this by finding edges of contrasting colors and blurring them together with the next pixel over, which reduces jagged edges by a lot. However, it does this to everything on the screen since it can't actually tell what's truly and edge and what isn't, so everything can end up blurry.

Then we have SMAA, which is post processing AA that uses similar edge calculation as MSAA, meaning it can have light performance requirements like FXAA while not blurring the entire screen. If you want a balance between performance and looks, go with this.

Something cool that most don't know is that you can often apply post processing AA from your video card, outside the game. This means you can do stuff like combine as much MSAA as your system can handle, then add on a small amount of SMAA (very low performance cost) and end up with AA greater than the sum of it's parts.