ENIAC (Electronic Numerical Integrator and Computer) is well known as a milestone in computing history. It was among the very first Turing-complete electronic computers. Before computers like ENIAC, Z3 and Harvard Mark I, computers were purpose-built for a single usage scenario. ENIAC and others heralded a new era of programmable general purpose computers, and indeed, kick started a whole new industry we now call software.
Human computers
As far back as the early industrial revolution, there were "computers". Or simply, people who could compute. For some tasks, it required real talent - such as mental arithmetic - while others were more menial.
World War II saw an incredible rise in computing. But before the mechanical and subsequent electronic computers, much of the computing were done by humans. They were largely women too, mostly working on military related calculations.
World's first programmers
Six such human computers - Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Meltzer, Fran Bilas, and Ruth Lichterman - were selected to program ENIAC.
This is, of course, before the era of the silicon transistor. Instead of miniscule transistors being photographed onto silicon, these computers were made up of physical mechanical and electrical components. ENIAC consisted of thousands of vacuum tubes, resistors, capacitors and crystal diodes. They were assembled together by an estimated 5 million manually soldered joints!
Programmers didn't just sit in a chair and write some code. Debugging wasn't simply looking through the code and fixing errors. Instead, the programmers had to dig through ENIAC's hundreds and thousands of components and millions of joints, and manually fix the bugs.
That is what these six programmers accomplished.
Forgotten pioneers
Most human computers were women because men perceived it as a banal profession. But when Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Meltzer, Fran Bilas, and Ruth Lichterman got ENIAC computing at unbelievable rates, the establishment men took notice. Hundreds of programmers took over the ENIAC project, while the six initial programmers were sidelined and forgotten.
When this famous photograph was released, they were written off as mere models! Or as the derogatory slang goes - "refrigerator ladies". For nearly half a decade, no one knew what they really accomplished.
ENIAC was largely used in calculations of military related programs. It was very high maintenance, but saved thousands of hours versus human computers.
Attorney Kathy Kleiman discovered that most of the original programmers were not invited to EINAC's 50th anniversary. She made it her life's mission to rediscover the legacy of these six women. This work has culminated in the film "The Computers: The Remarkable Story of the ENIAC Programmers" that you can watch Vimeo on Demand. We owe it to Kathy Kleiman and collaborators for bringing this important piece of history back to public consciousness.
This post concludes a trilogy of underappreciated and forgotten world's firsts - world's first scientist and world's first space pilot.
Further reading -
http://eniacprogrammers.org/
http://www.columbia.edu/cu/computinghistory/eniac.html
http://mentalfloss.com/article/53160/meet-refrigerator-ladies-who-programmed-eniac
http://pcfly.info/doc/Computers/18.pdf
All images from Wikimedia.