With financial backing from the likes of Michael Dell and other venture capitalists, open source upstart Nginx has edged out Microsoft IIS (Internet Information Server) to hold the title of second-most widely used Web server among all active websites. What's more, according to Netcraft's January 2012 Web Server Survey, Nginx over the past month has gained market share among all websites, whereas competitors Apache, Microsoft, and Google each lost share.

Nginx has made quite a splash since its creator Igor Syosev, along with Andrew Alexeev, co-founded the company last July. The platform, which debuted in 2004 and was designed for high-volume Web traffic, runs on some 25 percent of the world's 1,000 busiest websites, including Facebook, Zappos, Groupon, Hulu, Dropbox, and WordPress. Nginx last October received $3 million in funding from venture capital firms MSD Capital -- the Dell CEO's private investment company -- as well as BV Capital and Runa Capital.

According to Netcraft, Nginx now runs on 12.18 percent of all active websites -- that is, sites with unique content and aren't generated from templates -- for a total of around 22.2 million, according to Netcraft. In all, Netcraft found over 582 million websites for the January 2012 survey; around 18 million were active.

By comparison, Nginx ran on 11.6 percent of active sites (around 20.3 million in total) at the start of last December, meaning the open source platform's share jumped 0.57 percent. Microsoft IIS, by contrast, now runs on 12.14 percent of active websites, for a total of around 22.1 million. That represents a 0.17 percent drop compared to its December standing, when the platform powered 12.31 percent of active websites for a total of about 21.6 million.

Notably, although top-ranked Apache holds a healthy lead over the competition, running 57.93 percent of all active websites for a total of around 105.7 million, it too experienced a decline in overall share, down from 58.2 percent in December. Google, ranked No. 4 on Netcraft's list, saw its share dip as well, from 8.13 percent to 7.9 percent.

Taking into account servers for all sites covering all domains, Microsoft holds a healthy lead over Nginx, accounting for 14.46 percent of sites for a total of around 84.2 million. Nginx runs on 56.1 million of all sites, representing 9.63 percent. Apache dwarfs them both: 64.9 percent for a total of 378 million sites. Google rests in the fourth spot with a 7.9 percent market share, covering 14.4 million sites.

However, whereas Apache, Microsoft, and Google saw their market share drop, respectively, by 0.3 percent, 0.39 percent, and 0.07 percent since last month, Nginx's share jumped 0.78 percent.

Finally, among the world's 1 million busiest sites, Apache holds a market share of 64.4 percent (640,547 sites), down 0.36 percent since December; Microsoft's share is 14.99 percent (149,209 sites), down 0.01 percent; Nginx represents 8.49 percent (84,541 sites), up 0.28 percent month over month; and Google handles 2.4 percent (23,894 sites), an increase of 0.09 percent.

This article, "Nginx overtakes Microsoft IIS as No. 2 Web server," was originally published at InfoWorld.com. Get the first word on what the important tech news really means with the InfoWorld Tech Watch blog. For the latest business technology news, follow InfoWorld.com on Twitter.