Use examples when they help make things clearer.

Let me break it down for you using Ruby (the programming language) as an example:

Imagine you have a secret message that only certain people should be able to read. You don’t want anyone else snooping around, right? Well, that’s where encryption comes in! Encryption is like putting your message inside of a secret box with a lock on it. Only the person who has the key can open up the box and see what’s inside.

In Ruby (the programming language), you can use OpenSSL to encrypt data using AES-256-CFB encryption, which is a popular and secure algorithm for protecting sensitive information. Here’s an example:

# Generate a random key and IV (Initialization Vector) for AES-256-CFB encryption
# Creates a new instance of OpenSSL::Cipher with the specified algorithm (AES-256-CFB) and generates a random key and IV for encryption
cipher = OpenSSL::Cipher.new('AES-256-CFB')
key = cipher.random_key
iv = cipher.random_iv

# Your plaintext data (the message you want to encrypt)
plaintext = 'This is a secret message.'

# Encrypt the data using your key and IV
# Sets the key and IV for the cipher instance and encrypts the plaintext using the specified algorithm
cipher.key = key
cipher.iv = iv
encrypted_data = cipher.update(plaintext) + cipher.final

In this example, we first generate a random key and IV using the `random_key` and `random_iv` methods of the OpenSSL::Cipher class. Then, we set up our encryption object (cipher) with the AES-256-CFB algorithm and assign it both the key and IV that we generated earlier. Finally, we encrypt the plaintext data using the `update` method to process chunks of data at a time, followed by the `final` method to handle any remaining bits.

The resulting encrypted data is stored in the variable `encrypted_data`. To decrypt this data later on, you would use the same key and IV that were used during encryption:

# Create a new cipher object using the AES-256-CFB algorithm
cipher = OpenSSL::Cipher.new('AES-256-CFB')

# Set the key for the cipher object
cipher.key = key

# Set the initialization vector (IV) for the cipher object
cipher.iv = iv

# Use the `update` method to process chunks of data at a time and store the result in the variable `decrypted_data`
decrypted_data = cipher.update(encrypted_data)

# Use the `final` method to handle any remaining bits and add them to the `decrypted_data` variable
decrypted_data += cipher.final

# The resulting decrypted data is now stored in the `decrypted_data` variable

In this example, we set up our decryption object (cipher) with the same AES-256-CFB algorithm and assign it both the key and IV that were used during encryption. Then, we pass in the encrypted data to be decrypted using the `update` method to process chunks of data at a time, followed by the `final` method to handle any remaining bits.

The resulting decrypted data is stored in the variable `decrypted_data`. And that’s it! With Ruby (the programming language) and OpenSSL, you can easily encrypt and decrypt sensitive information using AES-256-CFB encryption for added security.