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Now, so far we have David, who wants to send a secret message to John.

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To do this, John generated a key pair.

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John also sent the public key to David.

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David has downloaded the public key and imported it into his key ring.

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So if we go to David's computer right here, we can see he has John's public key.

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So right now, David can encrypt data with John's public key.

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Send it to John.

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And that way John will be the only person who can decrypt this data because he is the only person that

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has his own private key.

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Now, you'll also notice an extra entry in here.

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I've actually created a key pair for David in this section right here, for the sake of completion.

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You don't have to do this because, like I said, all we need is John's public key to send data to John.

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And according to the example we're doing, David will be sending data to John.

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So all we need is John's public key.

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I just created a key pair here for David, just for the sake of completion so that you can see how this

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will work in a real life scenario.

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So we actually don't need to use this anymore because David already has the public key of John.

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So all you have to do is literally start typing the message that you want to send to do this.

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I'm just going to open a text editor and I'm just going to start composing the message.

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So for this, we're just going to say hello.

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This is a secret message sent from David to John.

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Now to encrypt this message, we're going to click on the recipients in here to set the person that

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we want to encrypt the message to.

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So first of all, as you can see, to prove our authority or to sign the message, we're going to be

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signing it as David, because we have David's private key and this is David's computer, and then we're

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going to encrypt it for myself so that I can actually read the message.

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And we're also going to tick this box to encrypt it for others.

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And here we're going to put the names or the public keys of the people that we want to share this with.

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So we want to send this to John.

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And therefore, I'm going to type John.

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And as you can see, I'll get his key entry suggested to me in here.

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So all I have to do is click this and that's it.

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The message is going to be encrypted for him using his public key and for myself using my public key

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so I can read it.

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And also it's going to be signed using my private key so that John can validate the integrity of the

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message and make sure that it is actually written or composed by David.

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Now that we're happy with the options, we're simply going to click on sign Encrypt.

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And as you can see, it's telling us that the signing and the encryption is successful.

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So all we have to do is go back to the notepad in here and we have the encrypted message in here.

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So right now you can just copy all of this and send it to John using any method of communication so

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you can send it as an instant message.

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You can send it in a chat room, you can send it as an email, you can even put it in a pastebin publicly

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where anybody can see your secret message.

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This is the beauty of PGP.

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You can put this anywhere and nobody will be able to see or read the content of this unless they have

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the private key of John.

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And like I said, if John is using PGP properly and he knows what he's doing, he should never share

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his private key.

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Therefore, he will be the only person in the world that is able to read the content of this message.

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Now, for this example, to make things easy, I'm going to go back to my email client and I'm just

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going to reply to this email.

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And we'll put our encrypted message in here.

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Keep in mind, I'm copying it from the start to the end.

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I'm going to click on Send and that's it.

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Send to John.

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So let's go to John's computer.

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We're going to go to his email account.

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We're going to refresh the inbox and we're going to click on the message that we just got.

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And as you can see, this message is encrypted.

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It's gibberish.

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We can't really see what David is trying to tell us.

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So we're going to right click and copy this message.

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We're going to go to Cleopatra.

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As you can see right now, we're in John's computer.

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John is in bold.

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So that means we have the private key for John and therefore, we should be able to decrypt this message.

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So we're going to click on the notepad again.

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We're going to paste the message.

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It's already in our clipboard.

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And instead of clicking on Encrypt this time we're going to say Decrypt and verify.

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It's going to ask me for the passphrase for John Wick because like I said, this is going to need to

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use the private key of John Wick to decrypt the message.

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Remember, we had to set a passphrase when we created this key pair, so I'm going to input it.

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And perfect.

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As you can see, we have the decrypted message right here.

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So now in this example, John created the key pair.

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He shared his public key with David, and David was the one encrypting the message and sending it back

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to John.

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Now, if John wants to send something back to David, we just have to do the reverse of the process.

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So David will just have to create his own key pair, share the public key with John and then John will

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be able to encrypt messages and share them with David and know that David would be the only one able

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to read the contents of the messages sent to him.