Containerization packages software applications with all their dependencies into isolated, portable units called containers. Unlike virtual machines (VMs) that require a full operating system (OS), containers share the host OS kernel while maintaining application isolation through features like Linux namespaces and cgroups.
Each container includes the application code, runtime, system tools, libraries and settings needed to run, all packaged as container images—read-only templates that serve as blueprints for creating containers. This approach can ensure consistent performance whether deployed on a developer’s laptop, testing environment, production data center or hybrid cloud infrastructure.
The concept of containerization and process isolation has been around for decades, but the emergence of Docker in 2013 transformed the landscape. Docker provided simple, enterprise-grade developer tools and a universal packaging approach that accelerated mainstream adoption.
Following Docker’s success, Kubernetes emerged as the dominant container orchestration platform, originally developed by Google and donated as an open source project to the Cloud Native Computing Foundation (CNCF) in 2014.
This technology stack forms the foundation on which container management tools and practices are built. Container engines like Docker are made to handle the runtime execution. An orchestration platform like Kubernetes manages the operational complexity of scheduling and automating the deployment, management and scaling of hundreds of thousands of containerized applications.
The powerful combination of Docker and Kubernetes has driven widespread enterprise adoption. A 2021 IBM survey found that 61% of respondents had incorporated containers into at least half of their new applications over the previous 2 years. The survey also revealed that 64% are planning similar adoption rates for future development.