Colossus & Other Early Computers

[Music] welcome to another video from explaining computers comm this time we're going to look at some amazing historic computers at the National Museum of computing this is located at Bletchley Park in my nightie Kingdom which during World War Two was a top-secret code-breaking facility here we have colossus the world's first electronic computer the machine was designed and built by a man called Tommy flowers with a prototype mark one colossus entering service in february 1944 a mark ii colossus was undeveloped with the first of these put into operation in june 1944 in total by the end of the war ten colossus computers were being used by the code breakers at Bletchley Park while Colossus is programmable it's not a general-purpose computer rather it was developed solely to help decipher encrypted German high command messages specifically Colossus was used to determine the settings of the Lorenz encryption machine that the Germans used to scramble each new communication as you can see Colossus is based on vacuum tube or thermionic valve technology with a mark 1 machine having about 1600 vacuum tubes and the mark 2 about two and a half thousand to prevent these notoriously delicate components from blowing it's important but they're never turned off Colossus has no RAM or other form of electronic or magnetic memory instead it's fed data from a continuous loop of punched paper tape that circulates around this bedstead at the end of the machine a paper tape can contain up to 25,000 5-bit characters and travels at up to 27 miles an hour amazingly the whole thing holds together and allows Colossus to process up to 5,000 characters of second colossus is programmed by manually setting the positions of the rows of switches and plugs that we see on several of its panels so unlike a modern computer Colossus has no operating system and cannot run high-level programming languages because it's not a general-purpose computer Colossus also only runs a specific application for which it was built with it switches and plugs being used to select desired algorithms and other programmable parameters while Colossus has lights to indicate operation it does not have a monitor star display rather final output is directed to this electric typewriter the specific hardware we're looking at here is a rebuild of a colossus mark ii constructed by a team led by tony sail between 1994 and 2007 this fully working computer now stands at exactly the same location in Bletchley Park as the original Colossus 9 it really is an amazing machine to behold and a recreation that makes you appreciate the extraordinary achievements of computing the early pioneers the noise it makes is also hypnotic and you can almost feel and mechanical pulse of Colossus resonating out from the path and deep into our computing future [Applause] while the Colossus computer we were just looking at the reconstruction here we have the world's oldest original working digital computer when it was first built it was known as a Harwell decadron and it was made at the Atomic Energy Research Establishment in Harwell and used 828 decadron counting tubes for program and data storage this enormous machine was built to automate tedious mathematical work its design also prioritized simplicity reliability and unattended operation over pure computational speed in practice this resulted in a computer but not much faster than a skilled mathematician and performing calculations but which does not get tired and which can work relentlessly for long periods as we look ahead to the 2020 and the math automation of many jobs by artificial intelligence it's interesting to reflect that this is where the trend for mental automation started the Harwell decadron first ran in 1951 entered service in 1952 and was used in Harwell until 1957 it was an offered as a prize in a competition and won while educational establishment in Wolverhampton here it became known as the witch or war the Haunter instrument the teaching computation from Harwell and remained in use until 1973 having been disassembled and kept in storage in 2009 the machine was delivered to the National Museum of computing for restoration where it was first rebooted in November 2012 to add to their collection the National Museum of computing is rebuilding a working replica of the EDSAC or electronic delay storage automatic calculator this is due to be completed in spring 2018 it is already very large and very impressive as somebody working on the project told me this is a computer where you can walk inside the CPU the final reconstructed EDSAC will have about a hundred and forty shelves of bowel base electronics supported across 12 racks and will weigh about two tons with about one thousand words or roughly three kilobytes of memory the machine we able to process about six hundred and fifty instructions a second the original edsac was designed in 1947 and run its first program in May 1949 at its home in the Cambridge University mathematical laboratory the machine is important because it was the first computer constructed for general use by people who had not built it edsac remained in operation until july 1958 and across its nine years of service proved invaluable to many Cambridge scientists and engineers three of these even won a Nobel Prize for work that depended on edsac calculations bringing us closer to the present day this is an icl2 966 mainframe and so is this and so is this this quite enormous machine fills a significant proportion of the museum's large systems gallery and was constructed somewhere between 1985 and 1987 its manufacturer was ICL or international computers Limited which between 1968 and 2002 with a very large british computing company after 33 cabinets on display five housed a processor while 20 are exchangeable hard drives that provide the machine with its storage the plastic containers you can see on top of several units are used to hold disks remove from the drives the large containers housed platters providing 200 megabytes of storage while the smaller ones contain 80 megabytes the icl2 966 machine was used by the tarmac construction company until 1999 when it was finally decommissioned because it was expected to fail as a result of the y2k problem or millennium bug for anybody with an interest in computing the National Museum of computing is an amazing place to visit in the modern world it's far too easy to forget how different early computers were the computers we enjoy today in this place provides a powerful reminder of the very beginnings of computing now in addition to other large systems we see here things like the Colossus and the EDSAC and the which and this extraordinary large ICL mainframe the museum's also got lots of other exhibit it's got these amazing Thermolite valves he's got these extraordinary large hard disk platters that you probably spotted earlier and it's also got lots of early pcs so many in fact I'm going to cover them separately in another video but now that's it for this time if you've enjoyed this video please press that like button if you haven't subscribed please subscribe and I hope to talk to you again very soon [Music] you

Channel: ExplainingComputers

Views: 105,188

Rating: 4.9639463 out of 5

Keywords: Colossus, Colossus computer, Bletchley Park, National Museum of Computing, EDSAC, early computers, history of computing, computer history, classic computing, classic computer, ICL2966, ICL 2966, ICL mainframe, ICL 2966 mainframe, valve, vaccum tube, computer, computing, Christopher, Barnatt, computing heritage, computer heritage, Colossus rebuild, EDSAC rebuild, Harwell Dekatron, Dekatron, Dekatron computer, paper tape, Tommy Flowers, oldest working computer, WITCH

Id: KkSxC9pFGZs

Length: 9min 28sec (568 seconds)

Published: Sun Jun 25 2017

Reddit Comments

[u/NerdyKirdahy]

Really cool. Weird though that while even the old American computers used the standard 1 and 0 to store data, retro British computers used 1 and OU.