As virtual machines are complex and not easy to manage, there is often a requirement to bring in flexibility to custom IT services. This is where containerization comes into play. The concept of containers is defined as follows: a container is an infrastructure independent sandbox running in a container environment, without an operating system in the container. You can easily move containers between environments, and you can scale by adding another container to an existing environment.

Items that are usually bundled into a container include the following:

• Applications
• Dependencies
• Libraries
• Binaries
• Configuration files
• Container services have been an approach of different solutions in the past and even came from the community. In the meantime, the following container solutions survived.