Containers

To understand containers, let's compare them to traditional virtual machines. While virtual machines virtualize hardware, containers virtualize the operating system. They abstract the application, along with all its dependencies, into one unit. Multiple containers can be hosted on one operating system running as an isolated process:

Figure 6.2 – Applications in containers

Containers bring the following advantages:

• Isolation: Applications can use their libraries without conflicting with libraries from other applications.
• Resource limitation: Applications can be limited to the resource's usage.
• Portability: Applications are self-contained with all their dependencies and are not tied to an OS or a cloud provider.
• Lightweight: The footprint of the application is much smaller as the containers share a common kernel.

The software that allows the containers to run is called the container runtime.

While there...