Containers and Docker

Containers are extremely popular nowadays, and with the increasing number of people using and praising Docker, they seem to be everywhere. It’s a hype, though containers in software are not even new. Based on Unix, container technologies have existed since the nineties. But now, with the emergence of social, mobile and web-scale apps, containers have become THE tool for application developers. Docker is the extremely popular open source tool which enables application packaging in containers.

A container is an isolated, resource controlled and portable operating environment. In contrast to virtualization, which refers to the act of creating a virtual machine to act like a real computer with an operating system, containers provide operating-system-level virtualization. This avoids the overhead of starting and maintaining virtual machines. They are a solution to get software to run reliably when moved from one computing environment to another.

As mentioned above, the main purpose of containers is to increase reliability and simplicity when moving computing environments. You can use one copy of an operating system to run multiple containers, each with a part of an application, which reduces needed system resources. A container is a lightweight, stand-alone, executable package of a piece of software that includes everything needed to run it. This makes them ready for use within half a minute of booting and with that, creates new possibilities for development and scaling. They isolate software from its surroundings and help reduce conflicts between teams running different software on the same infrastructure.

As Docker puts it, they are “the company driving the container movement and the only container platform provider to address every application across the hybrid cloud. It enables true independence between applications and infrastructure and developers and IT ops to unlock their potential and creates a model for better collaboration and innovation” (docker.com). It has simplified the use of containers by providing a suite of tools and handles, making it usable for everyone.