I've covered this previously here: https://news.ycombinator.com/item?id=5498682 https://news.ycombinator.com/item?id=5498682 In short, IA-32e was intel's inter

I've covered this previously here: https://news.ycombinator.com/item?id=5498682 https://news.ycombinator.com/item?id=5498682 In short, IA-32e was intel's internal implementation name, which was changed to EM64T which was changed again and is now called INTEL64. x86-64 / x86_64 / x64 are common names for the ISA created by various OSs, INTEL64 and AMD64 are implementations, the distinction is important because the implementations are not identical.