Why Windows 8 has a split personality

WINDOWS 8: Also called 'Metro', it's a touch-friendly environment of colourful panels and apps.
WINDOWS 8: Also called 'Metro', it's a touch-friendly environment of colourful panels and apps.

Microsoft is hanging a lot on Windows 8. The new operating system, intended for an October release, departs dramatically from the traditional desktop windows and icons. Instead, we'll get "Metro" – a touch-friendly environment of colourful panels and apps.

The departure is not complete, however; the familiar desktop is still there, barely changed, and the user can switch back and forth between conventional desktop programs and Metro apps. Why won't Microsoft make a clean break of it?

This isn't the first time this has happened.

Early in the 1980s Microsoft's Disk Operating System (MS-DOS, or just DOS) was the dominant operating system for the PC. It wasn't fancy, but it was cheap and it got the job done. Those who don't remember DOS didn't miss much. Those who remember are likely flashing back to the arcane commands and the cold sweat as they pressed enter and hoped for the best. Thank goodness that DOS is long gone.

Except it isn't, really. When the first version of Windows came along in 1985 it wasn't a complete operating system but a pretty layer on top of DOS, just one of many that appeared around the same time.

It took a while to catch on but it made the PC so much easier to use that by 1995 it was everywhere.

Windows 95, issued that year, included a number of dramatic changes and introduced many new features including now-familiar fixtures like the task bar and start menu. DOS was not cast aside, however. It had been merged into Windows and formed the foundation on which the new advanced features rested.

DOS programs could still run in a window on the desktop, or, if you really despised all the fancy windows and graphics you could disable them altogether and Windows would appear just like DOS.

This DOS heritage is responsible for many strange Windows quirks, which could take a book to explain.

The reason for this split personality was backwards compatibility. Microsoft had already developed an alternative Windows that wasn't based on DOS. But millions of people had DOS programs they still wanted to use. Many businesses still relied on DOS, and PC games almost all ran in DOS.

If Microsoft had tried to release a version of Windows 95 that couldn't run DOS programs, nobody would have bought it.

Flash forward 17 years and Microsoft finds itself in a similar situation. This time the problem is Windows – the conventional, desktop-based Windows. Touch and tablets are the next big thing, and Microsoft understandably wants to jump on that bandwagon with Metro, but at the same time it can't afford to alienate customers – especially large commercial customers – who have invested a lot of money in desktop software. So Windows 8, like Windows 95, will have a split personality and handle both.

These days, if you're not seen as brand new then you're history, which explains why Microsoft is emphasising the novelty of Windows 8. But things aren't always as new as they seem.

Check out the official Windows 8 release: preview.windows.com

A video demonstrating backwards compatibility: http://rasteri.blogspot.com/2011/03/chain-of-fools-upgrading-through-every.html

The Press