Discuss the core principles of cryptography and how it is applied in information security.

Cryptography, at its core, is the art and science of secure communication. It uses mathematical algorithms to transform data into an unreadable format, known as ciphertext, which can only be converted back into readable data (plaintext) with the proper key or mechanism. This practice is central to ensuring the confidentiality, integrity, authentication, and non-repudiation of data in information security. These core principles form the foundation of nearly all secure systems. Confidentiality ensures that only authorized individuals can access sensitive information. This is primarily achieved through encryption. Encryption algorithms scramble plaintext into ciphertext, and the reverse process, decryption, requires a specific key. Symmetric encryption algorithms use the same key for both encryption and decryption. For example, AES (Advanced Encryption Standard) is a widely used symmetric algorithm to encrypt files, network traffic, and databases. Asymmetric encryption algorithms, such as RSA (Rivest-Shamir-Adleman) use separate keys for encryption and decryption: a public key for encryption and a private key for decryption. This allows for secure key exchange over insecure channels. For example, when you connect to a website using HTTPS, the website's public key is used to encrypt a secret key that is then used for symmetric encryption. If data is encrypted with a specific encryption algorithm and its corresponding key, it cannot be viewed or interpreted without it. Integrity ensures that data has not been altered during transmission or storage. This is achieved using cryptographic hash functions, which produce a fixed....