Containerization is a type of virtualization that bundles code with its required environment. These bundles are called “containers”. Containers can be run in nearly all computing environments and are widely used in cloud computing.
How do Containers Work?
Containers work by providing a self-contained and isolated environment for software to run. They are typically managed in container orchestration systems, such as Kubernetes or Docker Swarm. These systems automate the work of managing and scheduling individual containers across clusters of servers.
Containers are built from container images, which provide specifications for the container and how it is instantiated. A container image can be thought of as a recipe, and the container is the dish made from following that recipe. Docker is a common platform for building, packaging, and distributing container images.
Containers vs. Virtual Machines
Containers and virtual machines are both types of virtualization technology that are used for similar purposes. However, a main difference is that containers virtualize at the operating system-level, and virtual machines virtualize at the hardware-level. This means that multiple containers can run on a single, shared operating system kernel, such as the Linux kernel. Virtual machines do not traditionally use a shared operating system, although some hypervisors now support container-like virtualization which can allow multiple virtual machines to use a single operating system kernel. Because multiple containers share the same kernel, they are typically considered less secure than virtual machines.
Benefits of Containerization
Containerization provides many benefits, such as:
Containers can be easily moved to different environments and operating systems. They can also be moved to different cloud providers, or different cloud or on-premise infrastructures without significant reconfiguration. This portability makes it easier to switch between cloud providers or adopt hybrid cloud infrastructures.
Containers can easily be scaled to handle changes in demand. For example, if a containerized web application had a sudden surge in web traffic, additional container instances can easily be added to handle the increased demand.
Containers are designed to be lightweight, and they are typically faster and more efficient than other forms of virtualization. One major reason for this is because containers do not have to boot an entire operating system, unlike traditional virtual machines. Additionally, because containers are designed to be small and efficient, more containers can be run on a single host.