Black History is infinity ➰ Every time you plug a device into your laptop, you’re using a language Mark Dean invented. But long before the 'Plug and Play' era, he was the silent architect turning a chaotic mess of wires into the world's first unified digital brain At IBM in the early 1980s, Dean co-invented the core architecture behind the personal computer, including the expansion bus that allowed hardware components to connect, communicate, and evolve. That breakthrough made computing modular, scalable, and accessible—unlocking the PC ecosystem that would reshape work, education, and daily life around the globe. Dean holds three of the nine original IBM PC patents. But his influence goes beyond invention. As a senior leader at IBM and later a professor of computer science, he helped guide how computing advanced—and who got to help build it. His work lives quietly inside the devices we use every day. Every document created. Every program run. Every system expanded. Mark Dean didn’t chase visibility. He engineered durability. This is what legacy looks like when it’s designed to scale—when innovation becomes infrastructure, and history becomes something we live inside rather than look back on. ➰ Legacy isn’t behind us. It’s on loop. 📍 Follow along as we continue highlighting the builders, the breakthroughs, and what comes next.