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

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John generated a keeper.

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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 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 keeper 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 so all we need is John's

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public key.

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I just created a keeper 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.

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So again we're gonna go to accessories.

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We're going to open my text editor and I'm just going to start composing the message.

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So for this we're just gonna say hello.

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This is a secret message sent from David to John.

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Now before sending this we're going to select all of this text.

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We're going to copy it.

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And then we're gonna go to the clipboard applet and we're going to click on sign encrypt clipboard with

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public key.

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We're going to click on this.

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And as you can see you get a list of all of the public key that you have on your computer.

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Now like I said all of the ones that start with tails are default public keys added in order to verify

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the integrity of packages downloaded from tells you don't want to select any of these.

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You want to make sure you select the contacts that you want to send their message to.

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And in our example we want to send the message to John Wick now this is perfectly fine.

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You can just select it like this and click on okay to encrypt the message.

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But in this case even you even David.

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So even the sender won't be able to see the contents of the message if you want to be able to decrypt

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the contents of the message yourself as well then you should take the entry for your own key.

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So this is David's computer.

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And if David wants to still be able to see the contents of the message that he is going to send he should

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take this box.

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Otherwise we can just tick John.

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And the only person in the world that will be able to read the content of this message will be John

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or anyone who has the private key.

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But if John is using BGP properly he should never share the private key with anybody.

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And therefore when we encrypt a message with his private key we can be sure that John will be the only

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person that can read the content of this message.

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So we're going to click on.

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OK.

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That's going to ask us if we trust this key we're going to say yes we do trust it.

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And as you can see in here you can see the icon of the clipboard has changed to indicate that the clipboard

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right now contains an encrypted text that represents the text that we copied already.

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So if and the same text editor in here if I just paste whatever that is in my clipboard you will see

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I'll get an encrypted message.

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And this is basically the content in here encrypted using John's public key.

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So right now you can't 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 chatroom you can send it as an e-mail.

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You can even put it in a pastebin publicly where anybody can see your message where anybody can see

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your secret message.

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This is the beauty of PDP.

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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 PDP properly and he knows what he is doing he should never share his

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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.

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I'm going to go back to my e-mail client and I'm just going to reply to this email and we'll put our

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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 sent 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 e-mail 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 so we're going to right click and copy this message

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and as soon as we copy it you'll notice the clipboard icon in here.

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Again changes to indicate a lock to indicate that the clipboard contains encrypted text.

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We're going to click on this and we're going to say I want to decrypt or verify my clipboard.

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That's going to ask me for the passphrase for my key for John Wicks key.

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Remember when we created this key we had to select a passphrase and that passphrase will always be required

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before you can use this private key.

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So I'm going to put the passphrase that I set when I created this key I'm going to click on.

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OK and perfect as you can see we can see the contents of the message saying hello.

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This is a secret message sent from David to John.

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So that's pretty much it.

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As you can see the receiver shares their public key with the sender the sender uses this public key

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to encrypt the message and then they can put the message anywhere or even share it publicly.

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It doesn't really matter because the only person that can read this message is the person who has the

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private key the private key never gets shared therefore this is a very very good and secure implementation.

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So now in this example John created the keeper.

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He shared his public key with David.

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And David was the one encrypting the message and sending it back 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 keeper share the public key with John.

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And then John will be able to encrypt messages and share them with David and know that David would be

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the only one able to read the contents of the messages sent to him.