Containers as a Service (CaaS) is a cloud service model that provides a managed platform for deploying, running, and orchestrating containerized applications without the overhead of managing underlying infrastructure. CaaS sits between traditional Infrastructure as a Service (IaaS) and Platform as a Service (PaaS), offering developers fine-grained control over containers while abstracting away complexity around servers, networking, and storage. It encompasses everything from container runtimes and orchestration engines to registries, networking layers, security scanners, and observability tools—all working together to enable scalable, portable, and efficient application delivery. The key insight that makes CaaS indispensable in 2026 is that containers have become the universal deployment unit, and CaaS platforms handle the entire lifecycle—from building and scanning images to routing traffic, scaling workloads, and ensuring high availability—so teams can focus on application logic rather than infrastructure plumbing. Understanding how these components integrate forms the foundation of modern cloud-native engineering.