# Container A container is a lightweight, portable unit of software that packages application code together with its dependencies, libraries, and runtime environment. Unlike virtual machines, containers share the host operating system's kernel, making them faster to start and more resource-efficient. Docker is the most widely used container runtime, and container images are typically stored in registries like Docker Hub or cloud-provider registries. Containers are defined by a Dockerfile or similar configuration that specifies the base image, dependencies, and startup commands. Containers are foundational to microservices architectures, where each service runs in its own container and communicates with others via APIs. Container orchestration platforms like Kubernetes manage the deployment, scaling, and networking of containerized applications. While serverless platforms eliminate the need to manage containers directly, many serverless runtimes (including some configurations of Cloudflare Workers) use container-like isolation under the hood. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.serverlessapigateway.com/glossary/c/container.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.