The '''graphics aperture remapping table''' ('''GART''')<ref>[http://support.amd.com/techdocs/25112.pdfSoftwarepdf Software Optimization Guide for AMD64 Processors]</ref> or '''AGP-GART''' when used with [[Accelerated Graphics Port]], sometimes known as the '''graphics translation table''' ('''GTT''')<ref>{{cite web|author=freedesktop.org|url=http://dri.freedesktop.org/wiki/GART|title=GART|accessdate=2010-03-05}}</ref>, and often misintepreted as '''graphics address remapping table''' is an [[IOMMU|I/O memory management unit]] (IOMMU) allowing the graphics card to perform a [[direct memory access]] (DMA) to the host system memory. Introduced by AMD for mapping of 32-bit AGP [[graphics card]]s accesses to the 64-bit memory space of the [[AMD64]] processors<ref>[https://pdfs.semanticscholar.org/60f1/35af3eb5253394f4ff944062a1b9e6a0c564.pdf Utilizing IOMMUs for Virtualization in Linux and Xen]</ref>, it was later reused for [[PCI Express]] (PCIe) as well.
GART is used as a means of data transfer between the [[primary storage|main memory]] and [[video memory]] through which buffers of [[texture mapping|textures]], [[polygon mesh]]es and other data are loaded, but can also be used to expand the amount of video memory available for graphics cards, particularly for cards with no dedicated video memory such as [[Intel HD Graphics]] processors.
