X86-64

64-bit extension of x86 architecture

x86-64 (also known as AMD64, x86_64, x64 and, rarely, Intel 64) is a 64-bit extension of the x86 instruction set. It was announced in 1999 and first available in the AMD Opteron family in 2003. It introduces two new operating modes: 64-bit mode and compatibility mode, along with a new four-level paging mechanism.

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