Microsoft Azure is a comprehensive cloud computing platform offering over 200 services spanning compute, storage, networking, databases, AI, and developer tools. Azure operates across 60+ global regions and provides infrastructure-as-a-service (IaaS), platform-as-a-service (PaaS), and serverless computing models for building, deploying, and managing applications. At its core, Azure uses resource groups as logical containers to organize resources, while subscriptions define billing boundaries and access control hierarchies. Understanding Azure's shared responsibility model is critical—Microsoft secures the physical infrastructure and host OS, while you secure your data, identity access, applications, and network controls depending on the service model you choose. The hierarchical organization (Management Groups → Subscriptions → Resource Groups → Resources) enables governance at scale through Azure Policy, RBAC, and cost management boundaries.