AWS's best-practices framework for designing secure, resilient, efficient, and cost-effective cloud architectures. It is structured around 6 pillars: Operational Excellence, Security, Reliability, Performance Efficiency, Cost Optimization, and Sustainability.
A recurring question on CLF-C02 and SAA-C03. You should memorize the 6 pillars. There is an AWS Well-Architected Tool for evaluating workloads. Question: which pillar addresses recovery from failures? Reliability.
AWS Well-Architected Framework is a concept that can show up on the exam. Check the full guide to see it in context.