The Internet: Crash Course Computer Science #29

Today, we’re going to talk about how the Internet works. Specifically, how that stream of characters you punch into your browser’s address bar, like “”, return this very website. Just to clarify we’re talking in a broader sense about that massive network of networks connecting millions of computers together, not just the World Wide Web, which is a portion of the Internet, and our topic for next week. Today, we’re going to focus on how data is passed back and forth – how a domain name is registered by the Domain Name System, and of course how the data requested or sent gets to the right person in little packets following standard Internet Protocol, or IP. We’ll also discuss two different approaches to transferring this data: Transmission Control Protocol, or TCP, when we need to be certain no information is lost, and User Datagram Protocol, or UDP, for those time sensitive applications – because nobody wants an email with missing text, but they also don’t want to get lag-fragged in their favorite first person shooter.

Want to run traceroute on your computer? See directions below. Remember you can replace “” with whatever website you want!

Traceroute on Windows
1. Press the Start Button
2. Type “CMD” and press “Enter”
3. In the Command Prompt type “tracert”

Traceroute on Mac
1. Click on the “Go” drop down menu
2. Click on “Utilities”
3. Open Terminal
4. Type “traceroute”

Traceroute on Linux
1. Open Terminal by typing CTRL+Alt+T
2. Type: “traceroute”

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