What Is a Container?

A container is a lightweight, portable, and isolated runtime environment that packages an application together with its dependencies. Unlike virtual machines, containers share the host operating system kernel while keeping processes, file systems, and network resources isolated.

This isolation ensures that applications run consistently across different environments, such as development, testing, and production. Containers can be quickly started, stopped, or replicated, making them highly efficient for modern cloud-native workloads. Core attributes of containers beyond isolation include:

• Portability: Applications run the same way on a developer’s laptop, in a data center, or in the cloud.
• Efficiency: Containers share the host OS kernel, which reduces overhead compared to traditional virtual machines.
• Scalability: Containers can be replicated and orchestrated using tools like Kubernetes to handle varying workloads.

Containers form the foundation of modern application deployment and orchestration by providing a consistent, efficient runtime environment.