x64osx

x64osx refers to the architecture of the macOS operating system when it is running on Intel x86-64 processors. This is in contrast to Apple's earlier operating systems that ran on PowerPC processors or Apple's current transition to ARM-based Apple Silicon chips. When Apple transitioned from PowerPC to Intel processors in 2006, they adopted the x86-64 instruction set, and macOS was subsequently developed and optimized for this architecture. This period, often referred to as the Intel era of Mac, saw a significant increase in performance and compatibility with a wider range of software, as many applications were already compiled for x86-64. The x64osx designation specifically highlights the 64-bit version of this Intel architecture used by macOS. Developers targeting this platform would compile their applications using tools that produced x86-64 machine code. The shift to Apple Silicon, starting with the M1 chip in late 2020, marked the end of the x64osx era for new Macs, though compatibility for x86-64 applications continues through Rosetta 2 emulation for a transitional period.