VRAM (Video Access Random Memory) is used to keep the images that your computer shows on the screen. When an image is meant to be displayed the processor will read it then write it to VRAM. This is then decoded and displayed on the screen. Images can be read and written by VRAM at the same time to prevent images from flickering. VRAM has several types, the most popular being Synchronous Graphics RAM which is synchronised with a clock, this means it handles data more efficiently and in one operation. Rambus Dynamic RAM is the best kind for video editing and the choice of many professionals.