x86-64

x86-64 is a 64-bit processing technology developed by AMD that debuted with the Opteron and Athlon 64 processor. x86-64 is also known as x64 and AMD64.

x86-64 enables 64-bit processing advantages such as increased memory space (up to 256TB) and processing more data per clock cycle. The technology is similar to Intel’s server-oriented IA-64. However, x86-64 made 64-bit computing more available to the mainstream consumer through its capacity to run 32-bit programs simultaneously without emulation or loss of performance.

Intel licenses x86-64 technology for use in their processors, much as AMD gets their x-86 from Intel.