The Chip Family Tree

Apple’s first computers ran on the MOS 6502, an 8-bit processor Steve Wozniak chose for the simplest possible reason: it cost about $25 when rival chips ran $175 or more. He could actually afford to design around it, and its clean instruction set let one person hand-build a whole computer.

The 6502 and its descendants powered the Apple I, the Apple II and the long line of IIs that made Apple a company. It was never the fastest chip on the market, but it was cheap, understandable and everywhere, and it bought Apple the years it needed to become an institution.

When Apple set out to build a computer with a graphical interface, it needed far more power than the 6502 could give. The Lisa and then the 1984 Macintosh ran on Motorola’s 68000, a 16/32-bit chip with the muscle to push a bitmapped screen, windows and a mouse pointer around in real time.

The 68k family carried the Mac for over a decade, from the 128K through the SE, the II series and the Quadras. By the mid-90s it had run out of headroom against a new generation of RISC processors, and Apple went looking for a successor.

In 1991 Apple, IBM and Motorola formed the AIM alliance to build PowerPC, a RISC architecture meant to leapfrog Intel. It powered the Power Macs, the iMac G3 that saved the company, and the G4 and G5 towers that became design landmarks.

It ended in a wall. The G5 ran so hot that the Power Mac G5 needed liquid cooling, and Apple never shipped the 3 GHz chip Steve Jobs had promised on stage, nor a G5 that could fit in a laptop. In 2005 Jobs announced the Mac would leave PowerPC behind.

For years Apple had secretly kept Mac OS X alive on Intel chips under a project called Marklar, just in case. When PowerPC stalled, that insurance paid off: Jobs revealed at WWDC 2005 that OS X had been living a double life on Intel all along, and every Mac switched within a year.

Intel Macs were fast, could run Windows through Boot Camp, and kept the Mac competitive for fifteen years. But Apple was tied to Intel’s roadmap and its delays, and its own A-series phone chips were quietly getting extraordinary. In 2020 Apple began the divorce.

In 1990 Apple co-founded Arm Ltd with Acorn and VLSI to build a low-power processor for a handheld it was dreaming up: the Newton. The 1993 Newton MessagePad ran on an ARM 610, a chip sipping power in a way nothing on a desktop needed to.

The Newton failed, but the bet did not. Selling down its Arm stake later helped fund Apple through its near-death years, and the architecture it had helped create was about to become the most important one in the whole company. It just took a detour through your pocket first.

The iPhone’s first chips were off-the-shelf ARM parts, but in 2010 the iPhone 4 and the original iPad shipped the A4, the first processor Apple designed itself. From there the A-series became a juggernaut: A7 brought 64-bit to phones before anyone else, and the line marched to today’s A19 Pro.

Year after year the A-series posted performance-per-watt numbers that embarrassed laptop chips. By the late 2010s the obvious question was no longer whether Apple could design a great processor, but why the Mac was still running someone else’s.

In November 2020 the M1 arrived: an A-series chip scaled up for a laptop, and it rewrote expectations overnight. A fanless MacBook Air outran Intel machines that ran hot and loud, and did it on battery. The Mac had come back to ARM, the architecture Apple helped create thirty years earlier.

The M-series has climbed ever since, from M1 through M5, and Pro, Max and Ultra variants that scale the same design from a thin Air up to the Mac Studio and Mac Pro. One architecture now runs across the iPhone, the iPad, the Watch and the Mac.

The Apple Watch runs on the S-series, built as a System in Package: an entire ARM-based computer, memory and all, sealed into a single tiny module so it could fit in a case you wear. Each generation, from the S1 to today, tunes the same idea for a device measured in millimetres and milliwatts.

The smallest branch of the family lives in AirPods. The W1 in the 2016 AirPods made Bluetooth pairing feel like magic, and the H1 and H2 that followed added always-on Siri, adaptive noise cancellation and spatial audio, all from a chip the size of a grain of rice.