10 pieces of software that changed the world

While everyone remembers an iconic piece of hardware from their computing past – that first, briefcase-sized Compaq laptop or the gorgeous Palm V – few look back fondly on a classic piece of software.

This feature aims to redress the balance, thrusting the spotlight on ten genre-defining pieces of code that changed not only people’s lives, but the whole world.

We canvassed the PC Pro team – including our experienced Real World contributors – to produce a shortlist of more than 30 classic software packages. We’ve whittled those down to a definitive top ten, including operating systems, design software and perhaps one or two surprises.

Vote for your favourite, and nominate your own world-changing software, by participating in our poll.

1. Windows 95

We debated long and hard about which version of Windows deserved to make this list. Windows 3.1 “finally brought maturity to the market and pretty much plummeted Apple into a decade of despair,” argued editor Tim Danton. And what about Windows XP? An operating system so stable and reliable that it remains the world’s most-used OS today, almost a decade after it was first launched.

But in terms of impact, there can be only one winner: Windows 95. Apple is the tech company associated with wide-eyed fanaticism, but never before or since have people queued around the block at midnight to get their hands on an operating system. Egged on by a free-spending Microsoft marketing machine, Windows 95 sent PCs into the mainstream.

It wasn’t merely advertising bucks that made Windows 95 world-changing. It reinvented the desktop UI and introduced the concept of “plug and play”. It’s also responsible for some of the less momentous landmarks in computing history: the Blue Screen of Death is a by-product of Windows 95.

So it had its flaws, but Windows 95 was the defining operating system of the home computing era, the one that made Bill Gates a household name, the one that gave many their first taste of a PC. And for that, we shall remain forever in its debt.

2. The SCA virus

In 1987, the SCA virus was spreading like wildfire through the Commodore Amiga community. It had been created by a group called the Swiss Cracking Association (hence the name) and was transmitted by sharing and swapping floppy disks.

SCA wasn’t the first computer virus – the idea dates back many decades – and it wasn’t even very destructive. It simply spread itself as widely as possible, and every so often displayed a message proclaiming, “something wonderful has happened… your Amiga is alive!”

SCA’s virulence was unprecedented at the time, and before long newspapers were running hysterical stories about computers all over the world being “possessed” by this new and malicious type of software. SCA can thus take dubious credit for turning malware from an academic curiosity into a global scare.

After that, inevitably, mischievous hackers quickly set out to top SCA with “better” viruses. Within a few years, hundreds of new viruses had appeared on a variety of platforms, including the 1989 AIDS trojan for MS-DOS, which encrypted user data and demanded payment for its return – a long way from SCA’s jokey modus operandi. Later came the likes of Melissa, Blaster, Code Red, Sobig, Sasser, Storm and all the other threats we’re still contending with today.

Those viruses gave rise to the multi-billion pound security software industry and the now common perception that running a PC without protection is socially irresponsible. Malware is now such big business that, even without SCA, it seems inevitable that it would have emerged sooner or later. But we’ll never know, thanks to that group of Swiss crackers who, back in 1987, let the malware genie out of the bottle.

3. Mosaic

Imagine a world where websites were just text documents with occasional links between pages. No Flash, no animation. In fact, no real graphics and not much functionality. That world was the World Wide Web back in 1993, which was only visible to those running Unix.

Luckily, Marc Andreessen and Eric Bina of the US National Center for Supercomputing Applications, or NCSA, saw this gloom and decided to create a snazzy web browser, which they called Mosaic. It allowed people to include images in-line with their text, and had sound and video support. It also introduced forms, sprinkling the seeds of the richly functional web we enjoy today.