The PC memory market has been one of the biggest growing in the industry for the past six or so years. DDR memory saw the introduction of a fast reliable memory that simply wasn't what Intel wanted to see. Intel's hopes and dreams lied with another type of (inferior) memory called RDRAM; they basically put all their eggs into one basket by hooking themselves up on a joint venture with RAMbus.
DDR soon showed us that it wasn't just able to counter the RDRAM memory, but when putting it into a dual channel configuration similar to what RDRAM worked on would give out more performance and at a cheaper price. Despite all of Intel's efforts to keep RDRAM alive, it was impossible now that DDR had entered the mass market with clear advantages.
Intel, while being beat back on RDRAM, did however make the big push on DDR2 memory, a higher clocked version of DDR RAM with a few extra features. The only issue that (eventually) surfaced with DDR2 memory was that we saw it hitting a wall at speeds of 1200MHz.
DDR3 memory is now the new big memory standard to come from the JEDEC group. DDR3 memory once again builds on the technology that DDR and DDR2 first laid down. DDR3 is still a parallel architecture rather than the serial nature that RDRAM tried to bring in. Like all of the DDR memory we have seen, the technology is derived from the old SDRAM modules that were so popular back when Socket 7 and Pentium II / III were at their peak.
Today we have some of the highest availably clocked DDR3 memory modules. We have 1800 MHz modules from Corsair and 1866 MHz modules from Super Talent. Today we hope to see just how far we can push them to and who will be king.