Of the top 25 websites in the world, only two aren't running on Linux. Those two, live.com and bing.com, both belong to Microsoft. Everyone else, Yahoo, eBay, Twitter, etc., etc., are running Linux.

According to Alexa's data, 96.3 percent of the top 1 million web servers are running Linux.

More and more web searches are a result of social media links. Collectively, the top 8 social networks drove 31.24 percent of overall traffic to sites. Facebook is number one, but if you also include Pinterest, Twitter, StumbleUpon, Reddit, Google+, LinkedIn, and YouTube you will still find them all running Linux.

So it might be true to say that the web runs on Linux.

Source: ZDNet