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# Uses

Cryptography is used in a variety of applications, including email, file sharing, blockchain, and secure communication.

### Email:

Cryptography is used to secure email communications. Email messages are typically encrypted using a symmetric-key algorithm, such as the Advanced Encryption Standard (AES). This ensures that only the sender and receiver of the email can read the contents of the message.

### Secure communication:

 Communications are typically encrypted using a symmetric-key algorithm, such as the AES. This ensures that only the parties involved in the communication can read the contents of the message.

### File sharing:

When a file is shared, it is typically encrypted using a public-key algorithm, such as the RSA algorithm. This ensures that only the intended recipient can decrypt and access the file.

### Blockchain

A blockchain is a distributed ledger that is used to record transactions. Each transaction is encrypted using a public-key algorithm, such as the Elliptic Curve Digital Signature Algorithm (ECDSA). This ensures that the transaction can only be decrypted and accessed by the parties involved in the transaction.