Docker is a software framework for building, running, and managing containers.
This section is relevant when installing an engine.
Cortex XSIAM maintains Docker images in the [Cortex Docker Hub organization](https://hub.docker.com/u/demisto/).
Each Python or PowerShell integration specifies its Docker image in its YAML file. If the image is not local, the engine downloads it from Docker Hub or the Cortex Container Registry. The integration then runs inside that container. For background information, see the [Docker documentation](https://docs.docker.com/) and [Using Docker](https://xsoar.pan.dev/docs/integrations/docker).
You can [download Docker images](https://xsoar.pan.dev/docs/reference/articles/download-packs-offline) with their content packs for offline installation.