Chapter 3. Technology Fundamentals

Solid familiarity with the following concepts will make your time with D3 a lot less frustrating and a lot more rewarding. Consider this a brief refresher course on Web-Making 101.


Beware! This is a pretty dense chapter, packed with years’ worth of web development knowledge, and nothing in here is specific to D3. I recommend skimming just the information that is new to you, and skipping the rest. You can always reference this chapter later as questions arise.

The Web

If you’re brand new to making web pages, you will now have to think about things that most people blissfully disregard every day, such as this: how does the web actually work?

We think of the web as a bunch of interlinked pages, but it’s really a collection of conversations between web servers and web clients (browsers).

The following scene is a dramatization of a typical such conversation that happens whenever you or anyone else clicks a link or types an address into your browser (meaning, this brief conversation is had about 88 zillion times every day):

CLIENT: I’d really like to know what’s going on over at I better call over there to get the latest info. [Silent sound of internet connection being established.]

SERVER: Hello, unknown web client! I am the server hosting What page would you like?

CLIENT: This morning, I am interested in the page at

SERVER: Of course. One moment.

Code is transmitted from ...

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