The discussion centers on the concept of using large prime numbers for encryption, specifically in the context of RSA cryptography. The term "large" is relative, as the effectiveness of encryption depends on the size of the primes used; larger keys provide greater security. While the product of two large primes is considered nearly unbreakable, advancements in computing power and parallel processing have made previously secure encryptions vulnerable over time, prompting the need for increasingly larger keys. Public key encryption, which utilizes both a public and private key, is widely adopted by corporations for secure communications. The conversation highlights the ongoing evolution of cryptographic standards in response to technological advancements.
