## Uninstall old versions
	
	sudo apt-get remove docker docker-engine docker.io containerd runc
    
## Install using the repository
### Set up the repository	
	
	sudo apt-get install ca-certificates curl gnupg lsb-release

### Add Docker’s official GPG key:
	
	curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dear                                                                             mor -o /usr/share/keyrings/docker-archive-keyring.gpg
	echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null 

## Install Docker Engine
### Update the apt package index, and install the latest version of Docker Engine and containerd, or go to the next step to install a specific version:	
	sudo apt-get update
	sudo apt-get install docker-ce docker-ce-cli containerd.io

### To install a specific version of Docker Engine, list the available versions in the repo, then select and install:
### a. List the versions available in your repo:
	
	apt-cache madison docker-ce
	
	 docker-ce | 5:20.10.11~3-0~ubuntu-bionic | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages
	 docker-ce | 5:20.10.10~3-0~ubuntu-bionic | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages
	 docker-ce | 5:20.10.9~3-0~ubuntu-bionic | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages
	 docker-ce | 5:20.10.8~3-0~ubuntu-bionic | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages

### b. Install a specific version using the version string from the second column, for example, 5:20.10.11~3-0~ubuntu-bionic.

	sudo apt-get install docker-ce=<VERSION_STRING> docker-ce-cli=<VERSION_STRING> containerd.io
	sudo apt-get install docker-ce=5:20.10.11~3-0~ubuntu-bionic docker-ce-cli=5:20.10.11~3-0~ubuntu-bionic containerd.io

## 	Verify that Docker Engine is installed correctly by running the hello-world image.

	sudo docker run hello-world
	
## Manage Docker as a non-root user
### To create the docker group and add your user

	sudo groupadd docker
	sudo usermod -aG docker $USER

### Log out and log back in so that your group membership is re-evaluated.

	newgrp docker 

### Verify that you can run docker commands without sudo

	docker run hello-world