The computing industry started booming after World War II. General Electric’s CEO refused to enter that market. But a small team of rebel employees bent the rules to forge on in secret. They created the GE 225. It was a giant leap in engineering that pushed computing from a niche market to the mainstream—sowing the seeds for today’s tech industry. Before the creation of general-purpose mainframes, computers were often built to perform a single function. William Ocasio recalls how GE’s first specialized computers, the ERMA, helped banks process thousands of transactions per day. John Joseph recounts how a few key GE employees hoodwinked their CEO into creating a computing department. Tomas Kellner explains how their work resulted in a revolutionary machine—the GE 225. And Joy Lisi Rankin describes how engineers at Dartmouth College adapted the GE 225 for time-sharing and used it to create BASIC—major milestones in making computing more accessible.

 If you want to read up on some of our research on mainframes, you can check out all our bonus material over at redhat.com/commandlineheroes . You’ll find extra content for every episode. Follow along with the episode transcript.