ALL ABOUT WEB SERVERS

The Web server is the basis of everything that happens with your Web page, and yet often people know nothing about it. Do you even know what Web server software is running on the machine? How about the machine's operating system?
For simple Web sites, these questions really don't matter. After all, a Web page that runs on Unix with a Netscape Server will usually run okay on a Windows machine with IIS. But once you decide you need more advanced features on your site (like CGI, database access, ASP, etc.), knowing what's on the back-end means the difference between things working and not.
The Operating System
Most Web servers are run on one of three Operating Systems:
1. Unix
2. Linux
3. Windows NT
You can generally tell a Windows NT machine by the extensions on the Web pages. For example, all the pages on Web Design/HTML @ About.com end in .htm. This hearkens back to DOS when file names were required to have a 3 character extension. Linux and Unix Web servers usually serve files with the extension .html.
Unix, Linux, and Windows are not the only operating systems for Web servers, just some of the most common. I have run Web servers on Windows 95 and MacOS. And just about any operating system that exists has at least one Web server for it, or the existing servers can be compiled to run on them.
The Servers
A Web server is just a program running on a computer. It provides access to Web pages via the Internet or other network. Servers also do things like track hits to the site, record and report error messages, and provide security.
Apache
This is possibly the world's most popular Web server. It is the most widely used and because it is released as "open source" and with no fee for use, it has had a lot of modifications and modules made for it. You can download the source code, and compile it for your machine, or you can download binary versions for many operating systems (like Windows, Solaris, Linux, OS/2, freebsd, and many more). There are many different add-ons for Apache, as well. The drawback to Apache is that there might not be as much immediate support for it as other commercial servers. However, there are many pay-for-support options now available. If you use Apache, you'll be in very good company.
Internet Information Services (IIS)
The Internet Information Servcies (IIS) is Microsoft's addition to the Web server arena. If you are running on a Windowws Server system, this might be the best solution for you to implement. It interfaces cleanly with the Windows Server OS, and you are backed by the support and power of Microsoft. The biggest drawback to this Web server is that Windows Server is very expensive. It is not meant for small businesses to run their Web services off, and unless you have all your data in Access and plan to run a solely Web based business, it is much more than a beginning Web development team needs. However, it's connections to ASP.Net and the ease with which you can connect to Access databases make it ideal for Web businesses.
Sun Java Web Server
The third big Web server of the group is the Sun Java Web Server. This is most often the server of choice for corporations that are using Unix Web server machines. The Sun Java Web Server offers some of the best of both Apache and IIS in that it is a supported Web server with strong backing by a well known company. It also has a lot of support with add-in components and APIs to give it more options. This is a good server if you are looking for good support and flexibility on a Unix platform