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The need for encryption

A huge amount of private data is sent around the Internet every day: emails with details about our personal lives, passwords that we type into login screens, tax documents that we upload to servers.
The Internet protocols send private data in packets on the same routes as everyone else's data, and unfortunately, attackers have figured out ways to look at the data whizzing around the Internet.
Illustrator of an attacker stealing data. A laptop is shown with a browser and a password input field. An arrow goes from the laptop to a server. Above the arrow, there's a pouch that contains the text "Be5tP@ssw0rd5ver" and a smiling attacker looking at the text.
That's where encryption comes in: encrypting data means that we scramble the original data to hide the meaning of the text, while still making it possible for the data to be unscrambled using a secret key.
Encryption enables two people (or computers!) to share private information over open networks.
Illustrator of an attacker unable to steal encrypted data. A laptop is shown with a browser and a password input field. An arrow goes from the laptop to a server. Above the arrow, there's a box that contains a long string of encrypted text that looks like nonsense and an unhappy attacker looking at the text.
Now we'll dive into the two most common types of encryption used in securing Internet communications: symmetric encryption and public key encryption.

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