# Introduction

#### Video Script

Welcome back, everyone. In today’s video, we’re going to be talking about universal computers. Now to pretty much pick up where we left off a while ago when we were talking about Boolean logic, Claude Shannon had just proposed a way to take electrical circuits and represent any Boolean logical statement with them. And so this was a huge turning point in the history of computer science. But how did we make the leap from Boolean logic on electrical circuits to the modern computers that we have today, and we’ll talk a little bit about that gap here today, but there will still be some missing parts that we’ll talk about later. But this brings us to Herman Hollerith, who at the time was a United States Census office employee, and he was tasked with coming up with a better way to calculate the census result. Because at the time, calculating the US census was incredibly slow. The 1880 census alone took eight years to tabulate, which really kind of defeats the purpose of a census, right? If you only know how many people you have in your country, eight years after the fact, the census was actually taken.

And so 10 years later, Herman had actually implemented a new system. And so in 1890, when he tabulated the US Census, then it only took one year to complete versus the eight years from the 1880 census. And this is even taking into account the 30% increase in population over that decade, which is pretty impressive, to say the least. So how did he do it? Well, just as Joseph Marie Jacquard had discovered, punch cards are really great way to organize and calculate information, particularly when you want that information to be read and used by machines. And so Hollerith was inspired by this fact. But really, actually, he was inspired by the way railroad conductors would actually use punch cards to track the gender and age and so forth from people buying tickets for the railroad. So not only did Herman Hollerith develop a new punch card in order to track US Census data, he also developed a machine to actually read it.

So this is an example of a Hollerith tabulating machine that was used in the 1890 census. So this machine could read the card and tabulate all of the information that was on them, and was also advanced enough to actually infer other facts and keep track of things like the number of married men and women. And depending on the data on the card, there is a compartment down you can kind of see towards the bottom right hand corner there. That was a storage box, for the cards and so depending on what kind of data was actually on the cards, a compartment in this storage box would open. So the operator that was using the machine could take the card from the machine and put it in the corresponding box. So essentially right it was auto sorting all of the census data, which was also pretty cool. But Hollerith continued to improve his designs and created several upgraded machines that could tabulate all sorts of data, not just census and donation, he would go on to create his own company, the Tabulating Machine Company, and a couple decades later, his company would join several under under a new name the Computing Tabulating Recording Company. But this was eventually renamed to be something else, the International Business Machines company, right. And many of you all know this company as IBM. Pretty cool, right?

This is something that I learned when coming to computer science, I had no idea how IBM got their start, but tabulating machines is pretty much where they come from. Now, this particular image from this slide is from the US Social Security Administration in 1936. This shows several IBM tabulating and sorting machines in use. And so they use these for all sorts of things as time progressed, and each one was able to keep track of all sorts of different kinds of information. One example could be tracking the sales of a particular person or company for the purpose of billing, right, or tabulating sales, and inside of a convenience store or something like that. Does all sorts of things, right. So things that were traditionally done on pen and paper or pencil and paper, and prone to a lot of human error. We could feed these punch cards through these machines and they would auto tabulate everything. For us, and they were pretty popular all the way through the 50s and 60s, until the computer started to take over really, but this pretty long time, right? About 30 years or so, for these tabulating machines, as they kind of took their grip. But we’ll talk a little bit here in just a second about the actual first computers that we actually had in the United States. But just as a quick little fun fact, we’ve talked briefly in a previous video How pretty much took a country torn by war before we actually started, or the world torn by war, really. Before we started to get a lot of advancements in computing technology. IBM was actually involved with selling these tabulating machines to the Nazi Party in Germany and may have inadvertently aided their attempts to catalog and later persecute the Jews. During the Holocaust, so a little bit of dark history behind IBM and their tabulating machines.

But we did take a big leap forward after the mark one was completed. So in 1943, the US Army and the University of Pennsylvania began working on a project that would be the successor to the mark one called the electrical numerical integrator and calculator or any ENIAC right. Scientists like acronyms, and sometimes they’re pretty good. Sometimes they’re not so great. But when the ENIAC was completed in 1946, it turned out to be about 1000 times faster than the mark one. But the ENIAC was so revolutionary. because it was the first all electric programmable computer that was truly general purpose. And we’ll talk about that here in just a little bit. But remember how we were talking about the Difference Engine that Charles Babbage created that was truly are the Difference Engine number two in the analytical engine that were truly general purpose computers, right. And so now we have the first all electric computer compared to the mark one, which still had a lot of the mechanical parts right had five horsepower. But the ENIAC ran almost continuously from 1946 to 1955. So had a pretty good long, long term operation here. Again, right had an insane number of parts right over 17,000 vacuum tubes that were used to run at 70,000 resistors, 10,000, capacitors and over 5 million hand soldered joints. If you have a hard time trying to figure out what’s wrong with your computer Now, imagine trying to debug and fix a computer that had so many different moving parts or so many different hand soldered parts is really kind of crazy to think about. But we’ll bring up the neck and the mark one and another lecture as well.

But I do kind of want to highlight a really big important part during this time frame, right? During the mark one and the ENIAC because remember, this is during World War Two, where a lot of the men were overseas fighting the war. And so a really far less known fact in computer science right? Early computer scientists were all women. So in the early days of computer science, the mark one ENIAC the majority of these machines and computers were being serviced, programmed and ran by women during the war. There’s this awesome documentary called the Top Secret Rosies, I would highly recommend watching the entire documentary. I’m sure you could probably find it streaming online somewhere. But this particular clip that I will show here in just a little bit, is just kind of a summary of the role of these women played during World War Two