servers

In our previous lesson, we discussed what the "local machine" is and we went over a brief rundown of what the internet is.

Now we're going to expand on that a little and talk briefly about servers and hosts.

what's a server?

A server(or internet server) is a computer that is set up to serve information to browsers of the internet.

Think of it like a coffee shop, we click a link(we order a cup of coffee), we get served a webpage on our local machine(we get served a cup a coffee at our table).

If we want our webpages to accessable to anybody browsing the net, then we need to have all of our webpage files stored on a server.

It is possible for you to set up your own local machine as a server, however i'm not going to teach you how to do that here and I'll explain why.

servers need to be on all the time

For starters, a server needs to running constantly and it also needs to be constantly connected to the internet in order for it to serve effectively. If you use your local machine as your server, any time it's switched off, rebooted or disconnected from the net, your website will be what is known as "down" or "offline". If your website is down or offline, nobody can access it.

servers use power

Secondly, chances are that you use your local machine for many other things, playing games, burning cd's, printing stuff, office work, emailing, instant messaging, surfing the net, playing music or any number of other things. Anytime that somebody views your website it's using your local machine's power and processing resources(meaning it makes your computer work harder). If you had 20 people browsing your website at once, it could slow down your computera little, making both your website load slower when people access it, and also making anything you are trying to do on your computer very slow.

Say your website got really popular and had 10,000 viewers or more per day, unless you had a state of the art mega-super-computer, this could bring all of your own personal use to a halt, not to mention that it could also wear out your computer.

servers upload rather than download

Thirdly, usually a home internet connection is geared for downloading rather than uploading.

If that line confused you, don't worry. Lets take break that down. Many people make the simple mistake of thinking that downloading only refers to manually downloading something like music or software(a computer prgram, eg an anti-virus program) that you conciously save onto your hard drive, but the truth is that anytime you go to a website, your local machine downloads all the files and pictures etc.... necessary to display that webpage in your browser(you'll usually find these files in your temporary internet files folder or cache).

If we look at the other side of things, on the server end, if you are downloading a webpage from a server, then the server of that webpage is "uploading" those files to your computer.

Yes you can upload files to the internet via a standard home internet connection however you will normally find that the upload speed given to you by your isp(internet service provider) is a lot slower and could have more limitations than the download speed and limits they give you. This could differ from from one isp to another but if you contact your isp's customer service, they can usually tell you your upload speeds and limits.

If you have a slow upload speed, then your webpages will load(download) slow for the people browsing your website.

servers need more security

Ok, if all if the above isn't enough to put you off using your own local machine as a server, there's also the issue of security.

Any computer, server or otherwise that is connected to the internet is vulnerable to being attacked and/or hijacked by hackers, viruses, trojans, spyware, adware etc, etc.....

Even with the most up to date anti-virus and firewall software, your computer is never 100% safe.

Servers are even more vulnerable than our pc at home for a couple of reasons. To start with, a server is already open to the public, it has to be to some extent in order for it to serve our webpages, so a lot more security measures need to be taken. On top of that, because the server is online constantly, it gives hackers all the time in the world to poke around at it, find all of it's vulnerabilities and exploit them.

Now who wants to deal with those headaches? Not me.

So let's move on to the next lesson here, where we'll discuss hosting.

Lesson added Saturday 9th August 2008