One thing that is wildly inconsistent in PC gaming is the quality of tooltips on the graphics options menu. You have games like StarCraft II which tell you which piece of hardware is being drawn on the most by a particular option and you have other games that just leave you to guess what the options mean, assuming they have any. Fortunately, in the case of the latter, I found this handy little infographic that explains some of the more prominent graphics options in PC gaming.
Infographic by Peek&co. Click to embiggen.