How to install Docker on Ubuntu 18.04

Prepare repository

sudo apt-get update && sudo apt-get -y install apt-transport-https ca-certificates curl software-properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable"
sudo apt-get update
apt-cache policy docker-ce

Install

sudo apt-get install docker-ce
sudo usermod -aG docker ${USER}
su - ${USER}

Validate

sudo systemctl status docker
docker info