Apple Begins the Intel Mac Era

Apple introduced its first Intel-based Macs in January 2006: an iMac and the new MacBook Pro. The switch ended more than a decade of PowerPC-based Macintosh hardware and moved the Mac onto the same x86 processor family used by most Windows PCs.

The difficult part was software compatibility. Applications compiled for PowerPC could not run natively on Intel processors, so Apple shipped Rosetta, a dynamic translation layer that converted PowerPC instructions as programs ran. Developers were encouraged to build “Universal Binary” applications containing both PowerPC and Intel code. This let Apple change CPU architecture without forcing users to replace all of their software at once.

The transition also changed what a Mac could do. Once Macs used Intel processors, running Windows directly on Apple hardware became practical, which led to Boot Camp a few months later.