The Influence of Plato IV System on Xerox PARC and the Alto
Indeed, the Plato IV system played a significant role in shaping the future of computing through its innovations that influenced the development of Xerox PARC's projects, including the iconic Xerox Alto.
Key Influences
The Plato IV system, developed in the early 1970s at the University of Illinois, was one of the pioneers in computer-assisted instruction (CAI). It featured an early graphical user interface (GUI), which inspired the Xerox PARC researchers to explore new applications in computing. Additionally, it was a networked system that enabled real-time collaboration, a concept that was integral to PARC's development of the Xerox Alto and other breakthrough technologies.
Historical Context and Personal Insights
In 1968, at the ARPA conference held at the University of Illinois, I had the opportunity to present my work, the Flex Machine, along with my colleague John Warnock. Our presentation highlighted the potential of a desktop personal computer with object-oriented programming and a multi-window user interface. It was in this environment that we were introduced to the pioneering work of the Plato IV system, which had a profound impact on our research and future projects.
Our visit to the University of Illinois included a tour of the Plato project, where we saw one of the first flat screen displays, which was then being developed for the Plato IV terminals. These displays, though power-intensive and limited in brightness, provided a glimpse into the future of visual computing. After Xerox PARC started up, we acquired one of these displays and connected it to a DG Nova minicomputer to experiment with new functionalities. The bistable pixels of the display, which didn't require continuous memory refresh, made it a promising technology for later applications.
The Impact on Xerox PARC
The visual capabilities of the Plato IV terminals, such as the cross-grid of infrared lights and sensors for low-resolution pointing, influenced our approach to user interaction. While the Plato IV system ran on a 1000-terminal time-sharing system, it was the concept of high-resolution displays that resonated with us at Xerox PARC. We envisioned a more powerful and flexible display system that could be integrated with a desktop personal computer, leading to the development of the Xerox Alto.
Our experiences with the Plato IV system, along with the ongoing research and innovations at Xerox PARC, fueled our goal of creating the Dynabook—a portable, interactive personal library and computing device. The Plato project's divergence from our path to build a more powerful and versatile system prompted us to innovate further, ultimately leading to the development of the Xerox Alto and other groundbreaking technologies at Xerox PARC.
Conclusion
The Plato IV system, though not a direct derivative of the Xerox Alto, contributed significantly to the innovative atmosphere at Xerox PARC. Its pioneering work in CAI, GUI, networking, and graphical displays laid the groundwork for future computing developments and inspired a generation of researchers and engineers to dream and innovate. The legacy of the Plato IV system is evident in the ongoing evolution of personal computing and the continued pursuit of interactive, powerful, and user-friendly technologies.