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So let's talk about the basics.

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So what exactly is cryptography, cryptography, sort of converting the brain text into unintelligible

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format called ciphertext?

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And why do we need this conversion means if you want to send a message to a friend by writing an e-mail

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on, write a letter and you put it into the envelope and send it to real post-box.

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And if other than your receiver, your friend, if anyone sees that it may lack a pregnancy rate and

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if the information content more true, then only the receiver should know that information for such

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a thing.

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We use the cryptography.

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So even though anyone sees this, it will be the unintelligible format.

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This is the ciphertext so normal other persons cannot read this until they have to convert.

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Again, the entries unintelligible format to the plaintext.

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So we are sending the unintelligible format and our friend also knows that I'm using some particular

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operation and I will tell that operator.

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So he'll do the reverse of that operation and he will get the plain text from this unintelligible format

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in that way, even though if anyone sees you are in an interview format, the thing that it's like gibberish

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or garbage on the receiver, that ciphertext is converted into production using the operation that I

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have written now cannot in this production, the unintelligible format.

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And this cryptographically policy and integrity president since no one should.

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Get that information other than senator and see what an integrity means, the message should be exactly

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what it should be.

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And in cryptography, we also make it so like it's like a hash of the file of the message.

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And that hash is chocolate.

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And if it matches, the nonlegal message is confirm that it was not damaged.

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If it is correct, it is damage done under the or somebody has modified this message.

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So cryptography maintains a privacy and integrity and cryptography is not registered.

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Yes.

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You do not register.

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You do not come from 10 years or 20 years ago.

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It from thousands of years ago.

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But they do something to the plain text message.

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So these ancient Greeks are Egyptians using some symbols which they have in their language, and they

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use these symbols instead of plain text and they use these words to convey the message to the receivers.

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And as you can see, the almost Daily Mirror images and they will decode the images and they use this

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cryptographic techniques.

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But today in hundreds, everyone is going to use these mathematical models, our mathematical operations,

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to convert this prediction to ciphertext.

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OK, now The Imitation Game, this is not any presentation, so this is the name of the movie and I

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highly recommend you to watch this because this is an education movie.

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And this film was portrayed by a lead actor, by Benedict Cumberbatch.

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And Dr. Phil, in this movie, we will see the biography of a great mathematician and also computer

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graphics card, Alan Turing.

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We are not Alan Turing like Turing machines, and he sided with the Germans Enigma machine in World

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War Two and so a lot of lives for England.

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And he Benedict Cumberbatch, portrayed the role fantastic there, and you will never get bored watching

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this movie.

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So once watch this, you will come to know that how Alan Turing deciphered the Enigma cipher.

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So in one not by the movie, but that guess you need to learn from others some skills.

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You need to learn from others, or even though sometimes others ideas may be useful for you.

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So you need to take every advantage for you to be or to solve a problem.

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So the talk in this movie, Alan Turing does, he gets a crew and with the crew, he just disappears

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within hours.

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So if you want to watch the movie, OK, stop the video right now and the next video.

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So I'm going to tell you how he found no.

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So actually, his girlfriend's friend arrives at the at some restaurant and then they discuss that she

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was inside.

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So they are excavations.

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And then she told that my boyfriend has cheated on me.

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So this Alan Turing asked, how did you know that he cheated on you?

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So she said that I destroyed him from the doubt.

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And then she followed her.

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She followed him.

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I don't know.

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So she said she said that I did.

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So Alan Turing came in.

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Alan Turing.

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Understood that what is the enigma so far, the message just contains a text that is already, I guess

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it.

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So what is Hitler and all those members does is they send the message like Morning Fighter to morning,

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good morning and early warning.

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So in that message, there will be some exact non vote like morning, evening, night.

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Right.

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So Alan Turing, the suit is what?

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And he put the this enigma decipher machine already some predicted values like morning and good morning,

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evening and night.

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He then he ran the Enigma decipher machine.

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So within hours, he got the plain text.

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So that's how he took that one to go.

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So some guessing values and he also saved some lives for the better.

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He's a great mathematician.

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And also, I highly recommend you to watch this movie.