Docker is reportedly going to be migrating all of their official images from an Ubuntu base to now using Alpine Linux.
Alpine Linux is the lightweight distribution built atop musl libc and BusyBox while using a GrSecurity-enhanced Linux kernel. Alpine Linux uses OpenRC as its init system. If you are unfamiliar with this "Small. Simple. Secure." distribution, you can learn more via AlpineLinux.org. The image for Alpine is a mere 5MB.
Read the full article here by Tux Machines