Back in the mists of time – I'm talking about 2000 here – when free software was still viewed by many as a rather exotic idea, I published a book detailing its history up to that point. Naturally, I wrote about Apache (the Web server, not the foundation) there, since even in those early days it was already the sectoral leader. As I pointed out:
With the visible and measurable success of Apache, shown in the monthly Netcraft reports detailing how many public Web servers were using which program, people were increasingly aware not only that free software was widely used by companies, but that it was running the single most important new development in computing for decades: the World Wide Web.
As such, Apache played a crucial role in preparing the ground for the later and continuing success of GNU/Linux, and for the dramatic uptake of open source programs in the late 1990s. In one respect, Apache still leads the field among free software projects. Although the debate still rages fiercely about whether open source software such as GNU/Linux can ever hope to best Microsoft, Apache has already done it.
That is, even at the beginning of this millennium, Apache had shown that free software could beat all-comers, and offer a solution that was simply better than anything else. That was a hugely important data point for the future, and helped pave the way for other open source code to do the same.
The above passage refers to the Netcraft reports. These are still going, and the latest one came out recently. Here's what it found:
Apache and nginx, both open source web servers, have lost market share this month whilst Microsoft gained significantly, up by 2.43 percentage points, to just shy of 20% of worldwide sites. For the second consecutive month, nginx is powering fewer sites than in the previous month's Web Server Survey, which is due, in part, to almost 2M sites moving from nginx and to Apache. Within the million busiest sites, a similar picture emerges: nginx lost over 4,000 busy sites, many of which have moved to Apache.
To put that in context, it's worth remembering that Microsoft's 20% share compares with Apache's 52%, which shows the abyss that separates them. The other important factor to note is that nginx, now firmly established as the "other" open source Web server, has clocked up a respectable 13%, which is not so far from Microsoft's. Cumulatively, free software represents nearly two-thirds of the entire global market.
In the 13 or so years since I wrote the passage quoted above, Apache has managed to hold on to its commanding lead over Microsoft, despite two massive – and doubtless massively expensive – campaigns by the latter to dethrone it, as evidenced on Netcraft's graphs by market share surges to nearly 40% a couple of times during that period. But once those campaigns were over, Microsoft fell back to the baseline 20% it retains today.
That shows something really important that goes beyond merely succeeding, which was why I wrote about Apache all those years ago. It shows that open source is no mere flash in the pan – some passing fad that gains market share briefly before sinking back. Apache became the leading server on the open Web and has remained the leader there.
That proves that open source is sustainable in the long term, which is crucially important for companies that are contemplating making it part of their critical infrastructure. You don't really care about something's market share: what you really care about is whether it is still going to be the best choice in one, two or five years' time. Apache has been the best for nearly two decades.
Is Apache the most important open source project? Opinions will naturally differ. Some will point out that Linux dominates the next key global computing platform – mobile devices such as smartphones and tablets. Others will note that Firefox has defended many kinds of critical online openness, without which the Internet would be hugely poorer. Both are enormous and indispensable successes.
But Apache has done something that no other open source project has managed (so far, at least): it has proved beyond the smallest shadow of a doubt that free software can not only become the undisputed market leader, but also stay there, year after year after year after year. That's both amazing and hugely important as an example for others to follow.