The Internet and the Web

The Internet and the Web are not the same.

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The Web is an application of the Internet composed of a series of protocols, languages and applications, such as HTTP, HTML, CSS, Javascript and the web browser.

Web History and Structure

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In 1989, Tim Berners-Lee proposed the WorldWideWeb as a means of organizing the documentation of the Large Hadron Collider (LHC) at CERN.

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It consisted of a browser/editor client that could render and edit the Hypertext Markup Language (HTML)

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and a server that would store the HTML files and send them to anyone on the internet with a browser/editor client who requested them using the Hypertext Transfer Protocol (HTTP).

Client-Server Model

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Berners-Lee's WorldWideWeb uses a client-server model that connects client to server using the Hypertext Transfer Protocol (HTTP).

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A client web browser makes a request for a set of documents using a Uniform Resource Locator (URL).

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The Domain Name System (DNS) collectively converts the URL into the unique Internet Prototcol (IP) address of the computer assigned to the URL and requests the desired resource.

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The requested resource (eg. /dir/file.html) is then retrieved by the server and sent back into the internet as a response.

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Once received, the web browser parses the file, perhaps requests additional resources (like images), and then renders out the files for the user once it has the files it needs.