Welcome to the Internet

Howard Abrams

2014 Nov 19

Created: 2016-09-26 Mon 21:55

Why Do We Learn

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Why Do We Learn History?

To understand why things are the way they are.

Do Computers Talk Directly?

Computers do "talk" to each other:

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But they don’t connect directly.

Once upon a time…

Each computer was an island

  • Hand friend a “floppy disk”
  • Type code printed in a magazine

handing-floppies.jpg

Modem Connection

Computer would “call” another computer

  • Very slow
  • Had to know the computer’s number
  • Computer had to be on

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https://www.youtube.com/watch?v=gnAAJ1FGudE

Web Invented in 1993

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Start talking about a human right to connect. –Tim Berners-Lee

Two "Types" of Computers

Either:

servers-4.png

Client is

clients.jpg

Servers live in Data Centers

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Difference:

  • We use a client to send or receive data
  • To and from a server

servers-4.png

How do we "Get" Data?

Since we don't know where the server is, we call it a cloud.

But if we don't know where the server is, how do we talk to it?

Internet Address: URL

http://www.howard.com/pers/resume.html

Like an address to your house…

Address "Parts"

http://www.howard.com/pers/resume.html

Every “address” has five parts:

Protocol http or https
Computer www
Domain howard.com
Folder pers
File name resume.html

Internet Communication

For something like Snapchat:

  • First photo is uploaded to server
  • Server stores photo
  • Client asks for any files
  • Server gives it the photo

servers-5.png

Internet is a Cloud

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What is a Web Page?

Each web page has parts:

  • Word organization (HTML)
  • Word appearance (CSS)
  • Interaction and Changes (JavaScript)
  • Images, movies (media)

Huh?

html-skeleton.jpg

HTML

<body>
  <h1>My Essay</h1>
  <p>
    This is the start of some words...
  </p>
  <img src="http://www.google.com/img/bananas.jpg" />
</body>

CSS

p {
    font-size: 24px;
    color: green;
    text-emphasis: italics;
}

JavaScript

  • Computer Language
  • Runs in the Browser
  • jQuery connects JavaScript to the parts of your HTML
Howard Abrams