The Story of Apple I: How Steve Wozniak Built a Complete Computer System Alone

Hello everyone, I’m the island owner Xiao Feng Ge. The annual leave passed quickly, and today is the first day back to work, so let’s discuss a simple topic.

Computers are extremely complex systems involving CPU, memory, compilers (programming languages), operating systems, and more. Is it possible for a single person to handle an entire computer system?

The answer is yes, and it was achieved as early as 1976 when one person built an entire computer system from hardware to software. The system looked like this:

The genius engineer behind this computer is the man on the right in the picture, Steve Wozniak (hereafter referred to as Woz).

He and Steve Jobs together built today’s Apple empire.

On March 5, 1975, the Homebrew Computer Club held its first meeting in Gordon French’s garage in Menlo Park, California. Woz was inspired by this gathering and immediately began designing his own computer system.

In the era before GitHub and Google, Woz single‑handedly completed the entire computer system, demonstrated it at the club, and even helped other members build their own systems—perhaps the origin of the open‑source spirit.

When product manager Steve Jobs decided to sell the circuit boards that Woz had made, he sold his car to fund the new company, while Woz sold his HP‑65 calculator. The fledgling company quickly received orders to produce a complete computer system, which became the Apple I. This marks the origin of Apple’s practice of selling fully integrated hardware‑software systems.

Woz’s design initially used a Motorola 6800 processor (he did not design the CPU himself) and 4 KB of memory (also off‑the‑shelf). On the software side, he wrote his own BASIC interpreter. In reality, the Apple I did not have an operating system; it only featured a machine‑language monitor, which was common on computers from the 1970s to 1980s.

The machine‑language monitor acted like a primitive shell, allowing users to input commands, view or modify memory contents, program in hexadecimal, inspect code, or run a program at a specific address. It occupied a 256‑byte memory space and can be regarded as the operating system of that era.

In July 1976, the Apple I began selling for $666.66, a price chosen because Woz liked repeated numbers. After a year, it was replaced by the Apple II, which made Apple a household name in the United States.

Decades later, the revolutionary iPhone was released, and Apple became the world’s most valuable company.

Even in the early 1970s, Woz did not design his own CPU or memory; he used existing components and focused on programming them. Designing a commercial‑grade processor, memory, storage, or operating system is far beyond the scope of a single individual.

Thus, modern computer building resembles assembling building blocks: you integrate ready‑made hardware and software, debug, and test. Even a wealthy company like Apple took years to develop its own desktop processor, relying on Intel beforehand.

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