How web sites work
An epic story of how rugbyheaven.com.au
delivers important news to my screen every
• What is a website and where does it live?
• How does our browser find a given website?
• How does our browser display a given website?
• What is a database and how does it work?
What is the Internet?
• The internet is like our office computer network but on a
• There are literally millions of computers in this networked
• Simply put the internet is an international network of
What is the World Wide Web?
• The www exists on the internet
• It’s a lose term to define the part of the internet that
everyone can see and use
What is a website?
• According to the wikipedia a website is a collection of
related web pages, images, videos or other digital assets
that are addressed with a common domain name
• Let’s be serious though, we all know what a website is.
We’ve all been to google.com, wikipedia.org or of course
Do websites actually exist in cyberspace?
• Websites live in specific locations on web servers
How do we find what we’re looking for?
• With all these computers and all this information available
on the www wouldn’t it be great if there was a uniformed
way of locating all the resources we’re looking for…
• Introducing the uniformed resource locator or URL for
How does a URL map to a web page?
• Domain names are part of a URL
• DNS servers map domain names to physical machines
Finally our browser has found our site
• Now our computer can open a dialogue between the browser and the
web server using the request-response model
Finally a web page
• This is what we expect to see on our screen
How does it happen?
• A request is made to the server
for a single specific file (in this
• A response is sent back to the
browser in the form of HTML
• Our browser reads the HTML
and renders it to our screens
• Why doesn’t it look anything like
the web site I know and love??
HTML is very simple
• Yes that kind of simple
• BUT it does do a couple of
things very well
HTML has friends
• HTML is very good at displaying
text / data and linking to other
• Links to other resources can be
overt or covert
• This page has been improved
slightly by including cascading
HTML and Images
• It’s still not quite right
• The Browser now needs to
request all the Images from the
• In the example we just saw there were 64 files downloaded
to the browser, they were combinations of css, js, jpg, gif
and swf’s… And it all happened so quickly
• A little closer to home, on the PhotoChains homepage
there are more than 130 separate files downloaded!!!
So who builds this?
• Basically everything we’ve seen so far is built by Keong or
a bunch of people like him
• And if web sites / pages never changed I’d be out of a job
A little bit of jargon
• Server side code versus client side code
So what does server side code do?
• Web pages are not all static, in fact most these days are
• Servers run pieces of code to deliver different and more
specific responses to the browser
• Server side rarely lives alone though, it’s usually coupled
with one or more databases (or databi if you want to
What is a Database?
• Think of Dom’s rolodex, it stores specific information
• The databases we use allow us create our own structure
• We now know what a website is and where it physically
• We also know how our computer finds that website
• And finally we know how a webpage gets displayed in our
• We know what a database is and a bit about how it works
• Thanks for listening, you can all be honourable techies for
the day… Because deep down I all know you want to be
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