Here is a nice overview of the web server usage statistics from the April 2007 Netcraft survey: http://www.serverwatch.com/stats/article.php/3670036.
| Server |
No. of
Sites |
Market Share |
No. of Sites
With .com domains |
| Apache |
66,899,485 |
58.86% |
36,803,903 |
| Microsoft-IIS |
35,377,426 |
31.13% |
22,721,673 |
| Unknown |
2,761,059 |
2.43% |
2,042,800 |
| Sun-ONE-Web-Server |
1,663,476 |
1.46% |
1,244,246 |
| lighttpd |
1,382,843 |
1.22% |
1,182,516 |
| Oversee |
845,404 |
0.74% |
726,754 |
| Zeus |
488,838 |
0.43% |
154,088 |
| Netscape-Enterprise |
241,852 |
0.21% |
122,194 |
| Rapidsite |
194,758 |
0.17% |
109,697 |
| tigershark |
189,791 |
0.17% |
144,721 |
| thttpd |
142,575 |
0.13% |
8,536 |
| Lotus Domino |
88,250 |
0.08% |
29,840 |
| AOLServer |
70,301 |
0.06% |
3,702 |
| Zope |
48,556 |
0.04% |
12,337 |
| WebLogic |
29,579 |
0.03% |
16,955 |
| WebSTAR |
28,334 |
0.02% |
17,036 |
| Stronghold |
22,465 |
0.02% |
13,751 |
| Oracle-Application-Server-10g |
17,617 |
0.02% |
7,298 |
| Squid |
15,950 |
0.01% |
4,674 |
| 4D_WebSTAR_S |
11,669 |
0.01% |
5,605 |
| WebSitePro |
9,353 |
0.01% |
4,723 |
| WebSite |
7,908 |
0.01% |
3,324 |
| Orion |
5,745 |
0.01% |
3,738 |
| Xitami |
4,602 |
0.00% |
3,248 |
| Roxen WebServer |
4,430 |
0.00% |
1,373 |
| Sambar |
4,260 |
0.00% |
1,765 |
| Abyss |
2,864 |
0.00% |
1,309 |
| Enterprise for NetWare |
1,819 |
0.00% |
489 |
| Netscape FastTrack Server |
1,472 |
0.00% |
604 |
| WN |
1,353 |
0.00% |
107 |
| WebSphere |
1,277 |
0.00% |
658 |
| JRun |
1,222 |
0.00% |
704 |
| NCSA HTTPd |
910 |
0.00% |
206 |
It shows an already widely-used and gaining in popularity web server called lighttpd that is being used for static content serving in some large-scale scenarios like YouTube and Wikipedia.