Datasheet

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How web sites work
Adobe Dreamweaver CS4 Digital Classroom
1
A simple  ow chart
What happens when you type in a web site address? Most people don’t even think about it; they
just type in a URL, and a web site appears in a  ash. They likely don’t realize how many things
are going on behind the scenes to make sure that pages gets delivered to their computers so that
they can do their shopping, check their e-mail, or research a project.
http://www.yoursite.com/
User Machine (client)
Web Host (server)
When you type in a URL or IP address, you are connecting to a remote computer (referred
to as a server) and downloading the documents, images, and resources necessary to reconstruct
the pages you will view at that site. Web pages aren’t delivered as a  nished product; your web
browser (Internet Explorer, Firefox, Safari, and so on) is responsible for reconstructing and
formatting the pages based on the HTML code included in the pages. HTML (Hypertext
Markup Language) is a simple, tag-based language that instructs your browser how and where
to insert and format pictures, text, and media  les. Web pages are written in HTML, and
Dreamweaver builds HTML for you behind the scenes as you construct your page in the
Design view.
An Internet Service Provider (ISP) enables you to connect to the Internet. Some well-known
ISPs include America Online and Earthlink. You view web pages over an Internet connection
using a browser, such as Internet Explorer, Firefox, or Safari. A browser can decipher and display
web pages and their content, including images, text, and video.
Domain names and IP addresses
When you type in a web site address, you usually enter the web site’s domain name (such as
eBay.com). The web site owner purchased this domain name and uses it to mask an IP address,
which is a numerical address used to locate and
dial up the pages and  les associated with a
speci c web site.
So how does the web know what domains match what IP address (and in turn, which web
sites)? It uses a Domain Name Service (DNS) server, which makes connections between
domain names and IP addresses.
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