It's good to know that it's not magic.
30000 feet – it's probably too close.
Data travels around the world at insane speeds,
theoretically limited by , the speed of light.
The URL. It describes where and how to retrieve a "thing" in a network of computers.
The scheme. It tells a computer which protocol to use for retrieving
Uhm, a protocol?
A fancy shortcut for saying "a set of rules that two machines use in order to communicate in a standard way."
* The Web is using the HTTP protocol, hence "http://".
The domain. One or more readable words that represent said "thing" on the Internet.
* Some say that ~40% of all Internet traffic goes through Google.
A huge network of devices (~10 billion) that communicate using the Internet Protocol (IP).
* One of Google's IPs: 188.8.131.52
The World Wide Web
A way to distribute information built on top of the Internet. It uses the HTTP protocol for communication.
* Email and IM are also built on top of the Internet.
Domains – why bother?
They are easier for humans to remember and they allow a device to change IP address without affecting other devices talking to it.
We talked about URLs, domains,
HTTP, the Internet and the Web. Now let's get down to business.
We will explore the journey from typing an address in your browser to a website appearing in front of your eyes. Boom.
Step 1: You type some things
Step 2: The browser searches for an IP address
Domain Name System (DNS): A global system of computers (nameservers) that governs domain names and translates domains into IP addresses.
Step 3: The browser creates an HTTP request
Step 4: An epic journey begins
By design, there is no central device that knows of all other devices.
* Much like the Postal Service.
We talked about keystrokes, HTTP requests and Internet routing. Next up, the server.
It's yet another computer. It runs software that "serves" requests from other computers.
* Not necessarily HTTP requests!
What runs on a server computer?
Reply to a web request
A three step process. By the end, the server will have an HTTP response ready to be sent back to the network.
Step 1: The Web Server reads the HTTP request
Step 2: The App Server creates the content
Step 3: The Web Server creates an HTTP response
The lang(s) of the Web
How does a browser know how to display a website? It's, yet another, standard!
Adds structure and semantics. Enhances regular text with "tags" which are machine-understandable.
Adds styling. Colours, positioning, dimensions, animations!
Adds interaction and logic. Clicks, mouse movements, timers, game logic etc.
An example webpage
<!DOCTYPE html> <html> <head> <title>Hello World</title> <link rel="stylesheet" href="style.css"> <script src="script.js"></script> </head> <body> <h1>#yolo</h1> </body> </html>