Steve Wozniak is the hardware engineer whose designs gave Apple Computer its first two products. The Computer History Museum holds a publicity photograph from April 1976, catalog record 102665473, that captures him at work: it shows Wozniak on the left examining the Apple I motherboard while Steve Jobs faces the camera, with the machine’s display reading a message about the computer being available at the Byte Shop. The image documents the partnership at its origin, with Wozniak in the role he kept throughout the founding period as the person who actually built the circuits.
Wozniak designed the Apple I as a single-board computer he could show off at the Homebrew Computer Club, the Silicon Valley hobbyist group where early microcomputer builders traded ideas. The Apple I Operation Manual, issued by Apple Computer Company in Palo Alto, reflects his approach: a complete working computer built around the MOS 6502 processor with a compact monitor program in read-only memory, achieving with a modest parts count what other designs of the era needed far more chips to do.
His most influential design was the Apple II. The Apple II Reference Manual, published by Apple in January 1978, documents the machine he engineered: a 6502 system with BASIC built into firmware, color graphics generated cleverly from the same memory the processor used, and a bank of expansion slots that opened the machine to outside hardware. The economy of that design, getting color, sound, and expandability out of a small number of components, was Wozniak’s signature and made the Apple II affordable enough to sell in volume.
Wozniak’s engineering extended past the main board. He went on to design the Apple II’s floppy disk controller, again reducing a normally complex subsystem to a spare, elegant circuit, which gave the Apple II fast and cheap disk storage and made it far more capable as a practical computer. That combination of processor, graphics, and storage, much of it from a single engineer, is what made the Apple II a durable platform for software like VisiCalc.
Wozniak’s importance is that he showed how much one engineer could accomplish when the new microprocessors put real computing power within reach of an individual. The Apple I and Apple II were, to an unusual degree, the work of a single designer, and they became the foundation of Apple and a cornerstone of the personal computer’s arrival in homes and schools.