Randomness and Entropy Questions

Understanding how to generate, evaluate, and use randomness securely in cryptographic systems. This includes knowledge of cryptographically secure pseudorandom number generators, true random number sources and hardware random number generators, entropy collection and estimation, the differences between kernel randomness interfaces such as dev random and dev urandom, seeding and reseeding strategies, library best practices for obtaining randomness, entropy health checks and tests, identifying weak or predictable randomness in code, and the consequences for key generation and protocol security.