What is Server? What Makes a Computer, A Server?
A server is nothing more than a computer. It has a hard drive, a CPU, memory and all of the things you will generally find in a home computer. Your home computer can be a server if you want it to be. A server by definition is just a computer which serves other computers. A web hosting server is nothing more than a computer which serves web pages to the computers requesting them; i.e., to the person running the internet browser. So while in the generalist sense every computer can be a server; correspondingly what makes a computer a good server?
A web hosting server is a server set up to perform web hosting tasks quickly and efficiently. A web hosting server does not need pretty graphics because typically it runs by itself without input from a person. It is essentially (after you set it up) fully automated. And unless it is necessary, it doesn’t have a monitor. (Of course like all things it needs maintenance from a qualified professional from time to time to ensure it is running efficiently).
A good web hosting server does have a few characteristics that make it different from a normal home computer. One of the characteristics is redundancy. Typically, a server has multiple hard drives which store the data. With a multiple hard drive system data is saved on more than one hard drive so in the event of a hard drive failure the redundant drive takes over exactly where the first hard drive failed. This process is known as RAID. Another redundancy you will find is that some servers will also have multiple network access cards (for faster input and output) and two power sources. The name of the game with servers is *reliability*.
Aiming for reliability with a server typically means that the latest and greatest is not necessary the best for a web hosting server. Web hosting servers typically wait until *all* the bugs are out of the hardware and software because they want their clients’ websites up at all times. (Of course servers should always have the latest and greatest security patches.) With these characteristics in mind sometimes it shocks the average person that most servers run lower end cpus. At the time of this writing the 3.0 Ghz chips are entering the market but you will find a lot of web sites hosted on Pentium III cpus. And quite frequently Celeron chips are used which range from 1.0 Ghz to 1.7 Ghz. The reason for this is two-fold: these chips generate less heat which is important to keep heat down in a server and web hosting does not generally demand much cpu processing. RAM (the computer’s main memory) is actually more important at times than the cpu. Typically a server should have 512 MB to 2 GB of memory, with 1 GB being a sweet spot for processing. But the question always arises-if a Pentium III does a very good job at web processing won’t a Xeon cpu or dual AMDs do better? Maybe-it really depends on what is on the server. If you have just web sites and they don’t use much scripting programs (PHP or Perl or CGI) or don’t have huge shopping sites like Amazon.com on them, a lower end cpu is going to perform pretty good. Of course the dual AMDs and Xeon are going to outperform the Pentium III but not as much as you are going to pay for the premium in pricing for the cpus and the additional requirements brought on by the increased heat (more fans, bigger cases, etc).