Hardware tiling and lighting. It is the ability for the graphics chips to handle in hardware the light effects instead of letting a software driver doing it. The surface of a 3D object is made of small virtual elements called tiles, or triangles. Each tile carries attributes like color, texture, transparency, reflectivity. The more tiles the more realistic the object. The lighting effects can be seen as how does a light positioned in the 3D realm reflect on an object. This is done by calculating the reflection angle of each tile, for the given light source, reflected towards the screen (the point of view). A nice object is made of thousands of tiles, so for each one these values are to be calculated in order to see the light reflecting on the object. Now picture a whole 3D world and many light sources, with all these calculations to be done, 30 times per second. If a 3D chip can do these calculuses itself, you can imagine how much processing power it offloads from the PC main processor. Most recent 3D cards do have this feature.
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