Chaos Engineering is a disciplined approach to identifying failures before they become outages by intentionally injecting controlled faults into systems. Born at Netflix from cloud migration challenges, this methodology transforms how organizations build resilience through systematic experimentation rather than reactive fire-fighting. The core insight: systems will fail — the question is whether you discover weaknesses during a planned experiment or during a 3 AM production incident. Unlike traditional testing that validates what you expect to work, chaos engineering reveals what you don't yet know can break.