Talking about Docker, it is a product, not a technology. Docker works on a technology which is containerization. It has been launched in 2013. Docker is based on virtualization.
Virtualization: Operating system virtualization is the use of software to allow a piece of hardware to run multiple operating system images at the same time. The technology got its start on mainframes decades ago, allowing administrators to avoid wasting expensive processing power.
Advantage of using Docker: -
It is very easy to launch Docker, you can launch your docker container within 2 or 3 seconds. To launch docker container you have to just need of container image. It may be centos: latest, ubuntu, python or any other. If you do not have docker image you can just pull it from the internet.
You can launch your separate container for your every separate work like to launch python use python2 or python3.
your virtual machine takes 30 minutes to install while it takes 2 or 3 seconds.
You can stop your container anytime and restart your container anytime. It’s a great benefit.
If you want to have your career in Docker then you must take up the following Docker Training Course. This course will give you in-depth knowledge about Docker and with a most valued certificate. For your reference, I am also mentioning a video tutorial which you must watch to learn more about Docker. .