Transcript The Internet

Internet vs WWW
 Pages vs Sites
 How the Internet Works
 Getting a Web Presence
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A network is a group of connected
computers that can interact with each
other and share resources
 The internet is a large network that spans
the entire Earth. It is actually a network
made up of many smaller networks that
are all combined.

The internet is more than just web pages
and the WWW (World Wide Web).
 The internet includes the www,
newsgroups, email and other shared
resources.
 So, the world wide web is a part of the
internet.

Do you know when the WWW was made available to the general
public?
A web page is a single file or page on
the world wide web that can display
images and text, links to other web
pages and can be designed to be
interactive.
 A web site is a collection of two or more
connected or linked web pages.

A browser is a program that allows a user
to view web pages on the World Wide
Web.
 Most popular browsers:
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Internet Explorer
Firefox
Google Chrome
Safari
Opera
Different browsers display web pages in
different ways.
 As a web page designer it is important to
design your page with at least Internet
Explorer and Firefox in mind – make it
work with both browsers!

On a network there are two types of
machines:
 A server is a computer that shares files
and other resources such as a printer
with other computers on a on a network.
 A client is a computer on a network that
accesses files or resources on another
computer (server).

The www is a large network made up of
many servers and clients
 Servers store web sites, and clients view
web sites
 A computer can be both a client and a
server at the same time

Is the computer you are sitting in front of
a server or client?
 Where is my website stored?
 How are you able to see it?
 How did I get the files available for you
to see?

When you type in a web address like
‘www.anything.com’,
 how does your browser know how to find
it?

There are many servers around the world
that store web pages for the world wide
web.
 Every computer – whether it’s a server or
client is given a unique identification
number when it connects to the internet.
 This unique number is called an I.P.
Address

An IP Address looks like the following:
 192.168.120.101
 There are four segments to an IP Address.
The numbers that make up each
segment can be from 0 – 255 (although
the very first segment can’t have a zero).

To connect to the internet and receive
an IP Address for your computer, you
must have an ISP (Internet Service
Provider).
 There are two types of ISP’s:

– Dial-up
– Broadband

Dial-up ISPs (approx 6% in U.S.)
– America Online
– Earthlink
– Net Zero

Broadband ISPs
– Charter
– AT&T DSL
– Mobile Providers
Dial-up internet access requires your
computer to dial a phone number to
connect and is very slow
 Broadband internet access is always
connected, and has much faster speeds
for loading web pages and
downloading files

Every time that you connect to your ISP, whether
by calling in to your dial-up connection or
restarting your broadband modem you get a new
IP address. This is called a dynamic IP address.
 If your computer keeps the same IP address always
and it never changes it is called a static IP address.

ACTIVITY:
Use the Internet to research 3 different Internet
Service Providers. You should write down the types
of services that providers offers and the pricing.
Servers that are storing or hosting a
website have static IP addresses. This
means that if you know the IP address for
a server you can always find that
webpage.
 Wouldn’t it be nice if there was a place
that stored that information? A place
that knew what the IP address was for
every server and what web pages were
stored there?

A DNS Server (Domain Name Service)
stores that information.
 But what if you had to remember an IP
address for every single web page that
you want to visit? Could you remember
them all?

– Instead of google.com what if you had to
remember that it was 64.233.160.0
A domain name is a group of letters that
represent the IP address for a particular
web site.
 anything.com is an example of a
domain name.
 cia.gov is a domain name.
 lost.tv is a domain name.


Instead of remembering IP addresses
– you just have to remember the domain
name

That’s what a DNS server does
– it keeps track of which domain names are
associated with which IP address

When you type in google.com
– the DNS server knows that means to actually
go to 74.125.224.72
URL (Uniform Resource Locator) is what
you type into your browser to request a
page.
 The URL contains the domain name, and
additional path information and the
protocol.
 The protocol is the http:// part at the
very beginning.

http (hypertext transfer protocol) tells the
browser that you are requesting a
document created using hypertext – what
we will be writing our web pages with.
 Most browsers do not require you to write
http:// or even www. before typing in the
rest of the address.

– http://www.google.com should be the same as
typing
– google.com

The additional path information is if the
webpage you are trying to view is in a
subfolder– http://www.google.com/folder/inhere/index.htm
Notice that for URLs we use / or forward slash.
 When using the path on our computer it is a
back slash or \

– C:\programs\microsoft\word.exe
– http://www.google.com/folder/index.htm
So to sum it all up 
 You type in the URL for a website into
your browser. Your browser is connected
to the internet through your ISP. It checks
the ISP’s DNS server to see what IP
address matches up with the domain
name and where it is located. The
request is sent to the server at that IP
address and the web page is sent back
to your browser.

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
You know how it works, you’ve made a
website, now you want to get it
published online so others can see it.
There are three things you have to do:
1. Register a domain name
2. Find a host
3. Upload your files
Pick a domain name – yourname.com or
whatever you want.
 You’ll need to check to make sure it
hasn’t been taken. You can do that at:

– www.internic.com/whois.html
– www.godaddy.com

You can also check to see if it is taken at
many other places as well.

Registering a domain name costs
money.
– Usually around $9.95/year.

There are many websites you can visit to
register your domain. A quick search in
google will provide you with a long list to
choose from.
The host is the company that you pay
money to allow you to store your website
files on their server.
 Some hosts also register domain names
as well.
 Some hosts are free, but do not allow
you to have your own domain name.

Again, searching google.com will provide
you with a long list of website hosts.
 The host will provide you with a specific
amount of disk space on which to save
your files
 More importantly the host provides your
website with an IP address that doesn’t
change.
 After finding a host, your domain is
registered on the name servers to point to
that IP address.

Dowloading is when you copy or move
files from another computer to your own
computer.
 Uploading is when you copy or move
files from your computer to another
computer.
 Now that you have a domain name and
a server to host your website, you have
to upload your website files to the server.

Uploading your files to the server is done
by using an FTP (File Transfer Protocol)
program.
 There are many free FTP programs
available – just search google!

Once you’ve uploaded your files, your
website is ready to go.
 It may take a day or two for your website
to show up after registering the domain
name and setting up your host.
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Bad Idea
Costs extra to have a static IP address, meaning an
IP address that never changes. Most ISPs provide
you with a dynamic IP address – meaning it
changes every time you connect.
Major security concerns
It will cause your connection to the internet to slow
to a crawl as more and more people visit your site.
Your page will load slowly for people who visit your
site
Many ISPs have contracts that specifically state
that you may not host your own website using the
IP address they assign you.
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Network
Internet
WWW (World Wide
Web)
Web page
Web site
Browser
URL (Uniform Resource
Locator)
Server
Client
IP Address
ISP (Internet Service
Provider)
 Hosting
 DNS (Domain Name
Service)
 Domain Name
 http (hypertext transfer
protocol)
 Downloading
 Uploading
