Understand images, containers, and storage drivers (Engine)

Understand images, containers, and storage drivers

To use storage drivers effectively, you must understand how Docker builds and stores images. Then, you need an understanding of how these images are used by containers. Finally, you’ll need a short introduction to the technologies that enable both images and container operations.

Images and layers

Each Docker image references a list of read-only layers that represent filesystem differences. Layers are stacked on top of each other to form a base for a container’s root filesystem. The diagram below shows the Ubuntu 15.04 image comprising 4 stacked image layers.

The Docker storage driver is responsible for stacking these layers and providing a single unified view.

When you create a new co