Explanation:
After you have read the storage driver overview, the next step is to choose the best storage driver for your workloads. In making this decision, there are three high-level factors to consider: If multiple storage drivers are supported in your kernel, Docker has a prioritized list of which storage driver to use if no storage driver is explicitly configured, assuming that the prerequisites for that storage driver are met: If aufs is available, default to it, because it is the oldest storage driver. However, it is not universally available.
Reference:
https://docs.docker.com/engine/userguide/storagedriver/selectadriver/