A brief history of the computer

MODERN TIMES

Many PC enthusiasts will be familiar with the way home computing has developed since then. As PC uptake continued and manufacturers tended towards a single, compatible platform, software vendors soon had access to a far wider and less complicated market. This was particularly true when it came to operating systems, the one bit of software that every computer needs. Just as it had with Basic for the Altair 8800, Microsoft got the contract to develop the operating system for the IBM-PC. Although this was distributed as PC-DOS, Microsoft cunningly retained the right to market its own MS-DOS, which it could supply to the growing number of IBM-compatible PCs.

An early photo of Microsoft founders Paul Allen and Bill Gates – courtesy of Microsoft

Microsoft has remained dominant ever since but its operating systems, like the hardware they run on, have continued to evolve. While the PC’s essential architecture remains unchanged, with any modern example theoretically able to run any early program, its subsystems have improved almost beyond recognition. New devices such as optical drives and sound cards have appeared while there have been several generations of data bus, disk interface and video card – each bringing faster speeds.

To date Moore’s Law has held true. While cramming 2,300 transistors onto Intel’s first microprocessor was at the cutting edge in 1971, today’s six-core Core i7 processor has more than a billion transistors – more than half a million times as many. At the same time, better designs and materials mean that modern processors run at far higher clock speeds. Intel’s 4004 ran at a maximum 740KHz and the Apollo Guidance Computer managed 1MHz, but today’s desktops can exceed 3GHz – three thousand times faster.

Improvements in hardware have enabled PCs to run anything from suites of office software through to graphics-rich games, but they’ve become more affordable in real terms too. At the same time, the public has become more computer-literate as computers have become more prevalent in our workplaces and schools. Cheap, compact processors have allowed digital technology to displace earlier standards in photography, music and other media, and our PCs help us edit, store and display the results.

Perhaps the most poignant illustration of the way in which massive computing power has become widely available came in 2007, after a working replica of a Mark II Colossus was completed at Bletchley Park. In a challenge to mark the occasion, enthusiasts were invited to compete against the mighty computer in a recreation of its wartime code-breaking role. German radio and computer enthusiast Joachim Schüth won the challenge; his 1.4GHz laptop decoding the Lorenz-encrypted message in just 46 seconds. The replica Colossus worked perfectly, but it took three and a quarter hours.