# Symmetric Key Cryptography

Symmetric key cryptography is an encryption technique that uses a secret key, which is confidential, to transfer data between a sender and receiver. This technique efficiently encrypts large amounts of data and is easy to implement.

## How Symmetric Key Cryptography Works

The secret key will rearrange the data into an unreadable form, also known as ciphertext, and the receiver will use the same key to decrypt the scrambled data into plaintext. In real-world usage, symmetric key cryptography can send an email message securely. Usually, the sender generates a secret key and encrypts the email message with that key. Once the recipient receives the email message, they use the same secret key to decrypt it. The secret key allows only the sender and recipient to read the message.

## Examples of Symmetric Key Cryptography

Symmetric Key Cryptography is a critical tool in securing data. Examples of algorithms used in symmetric key cryptography include:

- Advanced Encryption Standard (AES)
- Data Encryption Standard (DES)
- Triple DES (3DES)

Other use cases for this encryption technique include:

- The protection of sensitive data in military and government applications
- Transactions in banking and financial institutions
- Mobile device data encryption
- Secure communication between computers

## Advantages of Symmetric Key Cryptography

We have already established that symmetric key cryptography can provide a secure avenue of communication between a sender and receiver. Below are more advantages of using symmetric key cryptography:

- It is simple to use
- It is secure (as long as the secret key is long enough and well-protected)
- It is efficient because it requires less memory and processing power
- It is fast because it does not need to generate and exchange public and private keys