Forty years of IT

When Computing magazine launched in 1973, only the very largest companies had computers. Today, business couldn't function without them

The year is 1973. The "Barber boom" is fizzling out, and an energy crisis and the "three-day week" loom. But it's not all bad news: Computing magazine has just launched and in one of its first issues reports that the UK enjoyed a trade surplus in computing and IT in that year - quite possibly for the last time, at least as far as hardware is concerned.

Back in the 1970s, computers only existed in the very biggest of companies. Most corporate databases were held in massive rows of filing cabinets and on executive rolodexes. Letters were typed by secretaries in typing pools, and the "price gun" was the most important item of equipment in retail. Most shops, meanwhile, typically looked more like Arkwrights (from the television comedy, "Open All Hours") than the average Tesco superstore today.

However, the 1970s was also the crucible of the computer revolution: The eight-bit microprocessors that fuelled the first mass adoption of IT in homes and offices were all developed in the 1970s: the Zilog Z-80, the MOS Technology 6502, the Motorola 6809 and, of course, the Intel 8008 and 8088.

They powered the first generation of affordable computers, such as the Apple I and II, the Commodore Pet, the Tandy TRS-80, the Microtan-65, the Sinclair ZX-80 and, before all of them, the Altair 8800.

It was the launch of this relatively cheap kit computer in 1975 that inspired Bill Gates and Paul Allen to write a version of BASIC to run on it, which they subsequently adapted and licensed to other companies for use on their computers as interest in IT snowballed.

Many of them also built extensions to it to make it bespoke to their systems and needs, making it even easier for a generation of electronics enthusiasts and schoolchildren to get into computing and to start programming.

Microsoft Basic was also a key ingredient in the home computer revolution of the 1980s, as Sinclair's ZX-80 and ZX-81 gave way to the Sinclair Spectrum, and scores of other companies followed in its wake with alternative offerings: the Commodore-64 and Vic-20, the Camputers Lynx, the Oric-1 and Atmos, the Dragon-32, Acorn's BBC and Electron computers, and the Amstrad CPC-464.

Of course, there was also an awful lot of rubbish released too, such as the Mattel Aquarius, the Comx-35, the Coleco Adam, the Texet Lasor 200, the Apple Lisa, the IBM PC Junior and, quite possibly, the bug-tastic Sinclair QL. Enthusiasts therefore had to buy with care.

The revolution wasn't just about the technology pioneers, though. It also required an entrepreneurial spirit for people to recognise the opportunities in hardware, software, semiconductors and services: Bill Gates, Paul Allen, Steve Jobs, Chris Curry, Clive Sinclair, Dennis Hayes and Dale Heatherington, Robin Saxby, Hermann Hauser, Larry Ellison and many others.

Yet the home computer revolution, despite its immense influence, was also only a small part of the computer revolution that is still unfolding. Mainframes gave way to mini-computers, client-server computing, internet computing and, perhaps soon, we will be back again at centralised computing as a result of the cloud revolution.

Many fortunes, of course, have been made. But the money has shifted around the industry quickly, first from hardware to software, and now to services - but not necessarily the kind of IT services that enabled companies such as EDS, Hoskins, CSC, Cap Gemini and others to grow fat with SAP and Oracle enterprise resource planning (ERP) implementations in the 1980s and 1990s.

The mobile revolution, too, grew out of the innovations of the 1980s - and this aspect is ongoing. As microprocessors get more powerful, ever-smaller, yet more energy efficient, they also enable a greater amount of intelligence to be embedded into everyday devices and everyday life.

It is here, perhaps, that the next revolution in computing will come: with ARM and Intel, in particular, competing to provide the computing intelligence behind the so-called internet of things - and much else besides. Other companies and entrepreneurs, meanwhile, will compete to provide the infrastructure, the software and the services.

View our video to see the key highlights of the History of IT - and, perhaps, gain some insights into its future.

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