OSDev.org

hello,
can someone explain to me what software (operating systems- UNIX, Linux, WinNt, ...) and hardware (Computers, Network cards, ...) does someone need to build a web server.
Also, I would like to know how the "whois" service works.
Thanks in advance for any help.

I recommend http://apache2triad.sourceforge.net/

It installs everything you need for a nice state of the art server(apache, php, perl, tcl, python, mysql, ssl, ftp, and mail) which is alot easier than installing all that stuff seperately and configuring them to work with eachother since they get configured and installed for you.

Haveing a server doesn't require any special hardware or networks. Just as long as your ISP does not mind you using your computer as a server. Some ISP's do not allow it and will terminate your contract with them if you use your computer as a server. So it's best to check your ISP's contracts and info and such, and maybe even ask them if you can.

I do recommend a computer with plenty of memory and processing power, otherwise your site would appear to be slow. Also your ISP plays into this when it comes to speed/bandwidth, whatever those limits are on your bandwidth/speed would affect your server and it's use.

Ok, thanks, but what do Internet Service Providers have so special? How can someone connect to the Internet or set up a server without passing through an ISP?
Also, is it possible to make a private network by connecting two or more computers with let say, network interface cards (NICs), cables, routers, ... and installing a server operating system on one of them?

You can't create a connection without ISPs, since you'd need to rent the access to a regional backbone, and it can cost thousands per month...
When you're making a private network, you need to set up your router to pass the requests coming on port 80 onto the server.