5. Microprocessors were key to the development of the modern computer
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The early machines such as Colossus and ENIAC were limited by the fact that they had to be completely rewired whenever a new program was run. By the late 40s and early 50s developers were working on a new concept, the stored program computer, that would eliminate the need to rewire each time. The first computer with RAM storage, Baby, started work as a test project in 1948 and by 1951 the first general purpose computers, the Ferranti Mark 1, were at work.
These computers were still very large due to the need to use vacuum tubes, from 1955 on these tubes were replaced with transistors leading to a reduction in computer size and heat output. These were, in their turn, replaced with integrated semiconductor circuits. These were the direct antecedents of the microprocessor which made modern computers possible. The first commercially available microprocessor was the Intel 4004 which was launched in 1971, it used the new silicone based technology to miniaturize processing to a far greater extent than ever previously thought possible. These chips were sold as building blocks which could be used to customize the computers to the client’s specification; it was mostly used in calculators and could access 4KB of memory. This seems miniscule by today’s standards but it was revolutionary for the time. .
4. The first hard drives were bigger than fridges!
Storage has always been an issue for those using computers – in fact for many of us, storage is what drives our need to upgrade, whether it is our PC, our laptops, tablets or telephones. The original computers stored their data on large drums, these were rapidly replaced with disk storage which arrived on the scene in the 1950s. They were the size of two large fridges and held 5mb of data on 50 separate 24 inch disks.
In 1980 there was a step change and the precursor of the hard drive as we know it today was developed. Seagate (still leaders in the field of computer storage) developed a 5 mb hard disk drive which could be used with microcomputers. Over time these devices grew smaller and smaller and by 1998 it was possible to store 340mb on just 1 inch worth of disk. From this date the pace of change became exponential, by 2004 a 0.85 inch drive could store 2 GB of data and by 2015 manufacturers are talking about terabytes per square inch!
It is not just hard disks that have undergone a change, removable storage. In the 1970s the floppy disk had arrived, the first ones were huge at 8 inches (and really were floppy). They were the primary means of distributing programs for use on computers and for storing documents. In subsequent years floppy disks gave way to the smaller 3.5 inch rigid disks (still called floppies) that could fit, conveniently, in a shirt pocket and then later with CD Roms.
These days programs are typically downloaded over the internet and documents are stored either in the cloud or on USB drives. For those who still want access to the contents of their floppies, however, plug in ports complete with modern USB connections are available.
3. The famous Ctrl/Alt/Delete shortcut is a mistake!
Everyone knows that the first thing to do when a computer crashes is to press Control, Alt and Delete simultaneously. So popular has this maneuver become that it even has its own name, the ‘three fingered salute’.
This handy shortcut was, however, never meant to be released to the public at large. It was designed as a ‘soft reboot’ shortcut by IBM developer David Bradley who had become fed up with the length of time it was taking to reboot a computer with full memory retests every time there was a small glitch. The function was originally designed to use the control/alt and escape keys but because these could all be pressed by the left hand it was too easy to restart the computer by accident. The function was therefore switched to the now common control/alt/delete which needs two hands to implement.
This function was meant to be purely for internal use only, it was never intended to be published. It was included, by accident, in an IBM technical manual. The shortcut found a popular use, however, when Microsoft Windows became the operating system of choice. The early versions were buggy and would crash easily, gradually people became aware that the control/alt/delete shortcut could be used to save time and frustration when rebooting the system. The short cut works on almost all operating systems (Mac being the exception).