Installation On Ubuntu

1 - Add the new gpg key.

$ sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D

2 - add the repo location

$ sudo vi /etc/apt/sources.list.d/docker.list

3 - based on you version add deb https://apt.dockerproject.org/repo ubuntu-trusty main

4 - Update Package manager $ apt-get update

5 - install docker

sudo apt-get install docker-engine

6 - To test the installation

sudo service docker start

sudo docker version