End to end encryption is a way of making sure only the intended recipient of a message can read the message, even if that message has to be passed between many different places to reach where it’s going. This is necessary to protect your data on the internet because every bit of communication that happens, from loading websites to posting on social media to filling out online forms, all happens through the public medium of the internet.

If you’re curious how it actually works, imagine you’re sitting in school and you want to pass a note to your friend three seats away. You don’t want anyone in between to read the note, so before class you agreed on a special algorithm to use to scramble and unscramble the messages. Before you send a message, you’ll scramble it, and when you receive a message, you’ll unscramble it.

This works for a while, but eventually you realize: if anyone ever figures out your secret algorithm, they’ll be able to read all your messages. So, you come up with an even better algorithm. This one takes a password, and combines it with your message as it scrambles it such that anyone who gets the message also needs the password to unscramble it. Then you simply agree on a different password to use every day before class.

This works for a while, but eventually, it’s getting to gossip season and people are really trying to steal your messages and find out your juicy secrets. You decide that it’s too dangerous to share passwords before class because someone might overhear. So, you come up with an even crazier algorithm. This one requires two different passwords, one to scramble and one to unscramble. When you want to send a message, you now have to first pass a note to your friend saying you’d like to send a message. Then, they will come up with a scramble password and an unscramble password. They reply to you with the scrambling password. You then use the scrambling password to scramble your real message and you send it back to your friend. Finally, they use their unscrambling password to unscramble the message. This system is perfectly secure because you need the unscrambling password to read the message, and that password is never shared with anyone, so only your friend knows it.