PRIM-9

In 1973, a team of three researchers at Stanford Linear Accelerator Center (SLAC) — Mary Anne Fishkeller, Jerome Friedman, and the legendary John Tukey — created PRIM-9, the first-ever interactive computer graphics system designed specifically for exploring multivariate statistical data. The name stood for its core operations: Projection, Rotation, Isolation, and Masking, applied to data in up to 9 dimensions. Users could sit at a screen and dynamically rotate a point cloud in real time, isolate interesting subsets, and mask out irrelevant observations — all through direct manipulation of the display. This was 1973, when most statisticians were still working with printed tables and hand-drawn plots, so the idea that you could grab a high-dimensional dataset and spin it around on a screen was genuinely revolutionary. The system ran on an IBM 2250 graphics terminal connected to an IBM 360/91 mainframe, and Tukey — who had already transformed statistics with his exploratory data analysis philosophy — saw it as the natural next step: letting computers amplify human pattern recognition in ways that static charts never could. PRIM-9 directly inspired a lineage of interactive visualization tools, including later systems like XGobi and GGobi, and it established the foundational idea that data exploration should be a dynamic, human-in-the-loop conversation with the data, not a one-shot static summary.