To completely uninstall Docker:

Step 1

dpkg -l | grep -i docker

To identify what installed package you have:

Step 2

sudo apt-get purge -y docker-engine docker docker.io docker-ce docker-ce-cli docker-compose-plugin
sudo apt-get autoremove -y --purge docker-engine docker docker.io docker-ce docker-compose-plugin

The above commands will not remove images, containers, volumes, or user created configuration files on your host. If you wish to delete all images, containers, and volumes run the following commands:

`
sudo rm -rf /var/lib/docker /etc/docker
sudo rm /etc/apparmor.d/docker
sudo groupdel docker
sudo rm -rf /var/run/docker.sock
sudo rm -rf /var/lib/containerd
`
You have removed Docker from the system completely.