Apple's iPad now on sale in the US, and due here in a few weeks' time could renew interest in the idea of touch interfaces for business computers.
Touch interfaces are not a new idea, though; they predate the iPad, and even the iPhone, by more than two decades.
The honour of the first practical, touch-based PC goes to HP, which launched its HP-150 in the 1980s yes, the Eighties you know, big hair, Audi Quattros, that sort of thing.
The HP-150 used an array of infra-red sensors in front of a nine-inch CRT screen, which allowed the user to operate the interface without quite touching the monitor.
Unfortunately for HP, though, the computer was expensive, and although it could run MS-DOS, it was not fully IBM-PC compatible. The touch screen version failed to sell in large numbers. But unlike today's consumer-driven touch screen devices, the HP-150 was squarely aimed at the enterprise.
There is little doubt that devices such as the iPad will make more of an impact on the enterprise than the HP-150 ever did, not least because technology companies are so much better at marketing their wares now, than they were back in 1983.
HP, for its part, has soldiered on with touch-interface PC designs, such as its TouchSmart series. Other manufacturers are also adding touch-driven computers to its range, including a number of netbook devices based around the Android operating system.
Analysts, though, maintain that sales of such devices to business users will remain low. Gartner, for example, believes that just 10 per cent of PCs "sold to organisations in 2015 for mainstream knowledge workers" will have touch screens.
