The term 'web server' can mean two things - a computer/machine that hosts web sites (hardware) and a software that runs on such a machine and processes requests from browsers (also called client software). Generally, the context will make it very clear if the term "web server" is being used for the machine or the software.
According to Netcraft web server usage survey, Apache HTTP server is the most popular web server with a large market share of almost 60%. The popularity of Apache is followed by Microsoft's web server. The share of other web servers is very small compared to these two. Refer the Netcraft web server survey for further details.
I run the Apache web server on my Windows XP computer. I do this to test the scripts I write (in PHP and Perl) for web sites before I put them online. I find this process easier and quicker than trying to work off a remote server. So if you are planning to develop a web site that runs PHP or Perl scripts, I would definitely recommend that you get a copy of the Apache web server; learn how to install Apache on Windows 7 computer.
Here is a detailed and updated list of the most important and popular web servers:
-Apache web server - the HTTP web server
-Apache Tomcat
-Microsoft's Internet Information Services (IIS) Windows Server
-Nginx web server
-lighttpd
-Oracle Web Tier
Z-eus web server
select you want..all the best!