A very insightful presentation by Nick McGrath about a technical introduction to websites. It explains how a website works and where it lives.

1. How web sites work
An epic story of how rugbyheaven.com.au
delivers important news to my screen every
morning

2. Covering
• 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?

3. What is the Internet?
• The internet is like our office computer network but on a
global scale
• There are literally millions of computers in this networked
together
• Simply put the internet is an international network of
computers.

4. 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

5. 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
rugbyheaven.com.au

6. Do websites actually exist in cyberspace?
• No!!!
• Websites live in specific locations on web servers

7. 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
short
• http://www.rugbyheaven.com.au/news/200909.html

8. How does a URL map to a web page?
• Domain names are part of a URL
(http://www.rugbyheaven.com.au/news/200909.html)
• DNS servers map domain names to physical machines

9. 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

10. Finally a web page
• This is what we expect to see on our screen

11. How does it happen?
• A request is made to the server
for a single specific file (in this
case index.html)
• A response is sent back to the
browser in the form of HTML

12. 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??

13. HTML is very simple
• Yes that kind of simple
• BUT it does do a couple of
things very well

14. HTML has friends
• HTML is very good at displaying
text / data and linking to other
resources
• Links to other resources can be
overt or covert
• This page has been improved
slightly by including cascading
style sheets

15. HTML and Images
• It’s still not quite right
• The Browser now needs to
request all the Images from the
server too

16. We request this

17. It starts like this

18. Trasforms into this

19. And finally blossoms into this

20. Statistics
• 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!!!

21. 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

22. A little bit of jargon
• Server side code versus client side code

23. So what does server side code do?
• Web pages are not all static, in fact most these days are
dynamic
• 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
impress)

24. What is a Database?
• Think of Dom’s rolodex, it stores specific information
• The databases we use allow us create our own structure

25. Finally
• We now know what a website is and where it physically
lives
• We also know how our computer finds that website
• And finally we know how a webpage gets displayed in our
browser
• We know what a database is and a bit about how it works

26. Honourable techies
• Thanks for listening, you can all be honourable techies for
the day… Because deep down I all know you want to be