True Randomness vs Pseudorandomness

Cryptographic security depends fundamentally on unpredictability. If an attacker can predict your key, IV, or nonce — even partially — the entire cryptographic system may collapse. Weak randomness has caused catastrophic real-world breaks.

TRNGs harvest physical entropy: thermal noise in resistors, shot noise in reverse-biased diodes, radioactive decay, mouse movements, keystroke timings, disk seek latencies. These are genuinely unpredictable physical phenomena.