Part of the memory that is used to store the texture maps. Usually a separate block of memory (separated from the Frame and Z-buffer). There is 2Mb on most cards while the powerVR based cards have 4Mb. Texture maps can be stored in different formats : color depth, size (32x32 up to 256x256 pixels). The pixels of a texture map are usually referred to as Texels. The more Texture Memory your card has the more different texture maps can be used in a scene. This allows more MIP-levels or more different ones to avoid repetition of the same texture maps over and over, gives more variation and more realism to the scene. Some software companies are complaining that 2Mb of texture ram is not enough. The general rule is the more the better but watch our for bandwidth problems...