Because graphics are so important to computers (and especially computers designed to play video games), there are microprocessors dedicated only to creating and displaying computer graphics. This processor is called the Graphic Processing Unit (GPU). One of the most anticipated aspects of the PlayStation 3 is the new GPU that was created for it -- the RSX "Reality Synthesizer."
Sony designed the RSX with graphics-card manufacturer Nvidia. The RSX is based on Nvidia's GeForce graphics technology. It's a 550-MHz, 300-million-transistor graphics chip. To put that in perspective, according to this Nvidia press release, the number of transistors on the RSX is "more than the total number of transistors in both the central processing units and the graphics processing units of the three leading current-generation systems, combined."
Unlike the GPU in the Xbox 360, the RSX is built on the traditional independent vertex/pixel shader architecture. Shaders are computer programs that determine the final look of what you see on the screen when you're looking at computer animation. To learn about shaders, see our answer to this question, "What are Gouraud shading and texture mapping in 3-D video games?"
All of this translates to a level of graphic detail never before seen on a video-game console. With one HDMI output, the PlayStation 3 supports 480i, 480p, 720p, 1080i and 1080p.