Haven’t been following up on hardware. I’ve actually read these numerous times but keep forgetting. I needed to look up some PC specs today, so its now here for my own reference.
Intel Core is the series of Intel’s 32-bit dual-core processors. Intel Core Duo is the one with the dual core, and the Intel Core Solo is the one with dual core, but only one active. According to Wikipedia, it’s so that Intel can sell those with manufacturing defects on one core but not the other. Sounds logical to me, but can’t find supporting information elsewhere.
Intel Core 2 is the 64-bit series. So Intel Core 2 Duo means a 64-bit dual core processor, and Intel Core 2 Quad are the 64-bit quad cores.
On the other side, there was this (old) HyperThreading technology by Intel, which also have a “dual-core” impression because it shows up as 2 processors on XP. However its actually just one processor that simulates an additional one for doing useful work during otherwise idle cycles.
AMD’s naming is 64 means 64-bit, and X2 means dual core. So you have series like Athlon 64, Athlon 64 X2, Turion 64, Turion 64 X2.