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Welcome to Lesson 3, where we delve into the heart of blockchain technology, cryptography.

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Prepare to unlock the secrets of how this ancient art reborn in the digital age fortifies

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the blockchain against threats and ensures its integrity.

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What is cryptography?

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Imagine a secret language known only to you and your friends.

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In the digital world, cryptography plays a similar role.

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It transforms information into a secure format, ensuring that only those who are meant to understand

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it can.

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In the realm of blockchain, cryptography is like a digital lock and key, safeguarding your

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digital assets from prying eyes.

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Did you know cryptography's roots trace back to ancient civilizations like the Egyptians.

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Today, it forms the backbone of blockchain technology, securing digital transactions worldwide,

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the role of cryptography in blockchain.

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In blockchain, cryptography secures transactions, protects data integrity, and prevents unauthorized

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access.

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It's akin to sending a locked box through the mail, where only the recipient has the

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key.

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From DIGITAL's signature is to hash functions, cryptography is the invisible guardian of blockchain's

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integrity, cryptography and action, real world applications.

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Let's break down the cryptographic elements of blockchain through practical examples.

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Digital signatures.

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Imagine Alice sending Bitcoin to Bob.

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She signs the transaction with her private key, creating a unique digital signature that

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no one else can replicate.

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Hash functions.

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Every transaction and block in blockchain has a unique hash.

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It's like a digital fingerprint that changes completely, with even the slightest alteration

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in data.

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Public private key.

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Encryption.

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Alice sends a message to Bob, encrypting it with his public key.

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Only Bob can decrypt it with his private key, ensuring the message remains confidential.

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Exploring blockchain's cryptographic techniques.

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Blockchain uses hash functions, digital signatures, and public private key cryptography to maintain

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its fortitude.

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These techniques collectively form a fortress, protecting the blockchain from external

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threats.

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Digital signatures.

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The seal of authenticity.

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In blockchain, a digital signature is your personal stamp of approval.

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It proves that a transaction genuinely came from you and hasn't been altered.

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Fun fact.

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Digital signatures.

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The new autographs.

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There are more digital signatures made on the Bitcoin network each day than there are

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autographs of celebrities in a year.

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Hash functions.

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The magic formulas of blockchain.

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Hash functions are the magical math formulas of the blockchain.

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They transform any data into a unique code, ensuring the data remains untouched and

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authentic.

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As we conclude this lesson, remember that cryptography in blockchain isn't just a technical

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feature.

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It's the embodiment of trust and security in the digital world, making blockchain a reliable

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and revolutionary technology.