What are containers and virtual machines?

Containers and virtual machines are technologies that provide isolated environments for running software applications. They’re used in deploying and managing applications, and they help address challenges related to compatibility, portability, and resource utilization.


How are containers and virtual machines similar?

Both containers and virtual machines are designed to encapsulate an application along with its environment. This encapsulation includes the application itself, its dependencies, libraries, and other binaries. The goal is to enable the application to run reliably and consistently across different computing environments.


How are containers and virtual machines different?

The key difference between containers and virtual machines lies in their architectural approach. Virtual machines each contain a full copy of an operating system, a virtual copy of the hardware that the OS runs on, and an application and its associated libraries and dependencies.

Containers, on the other hand, share the host system’s operating system and isolate just the applications from each other. Each container includes the application and its dependencies. This makes containers more lightweight and requires less overhead than VMs.


What are the advantages of containers?

Containers are lightweight, start up quickly, and require less computational resources than virtual machines, as they share the host system’s OS kernel. This efficiency means you can have more containers than VMs on a given host. Containers are also highly portable, as the container encapsulates everything the application needs to run.


What are the advantages of virtual machines?

Virtual machines offer stronger isolation than containers, as each VM runs its own operating system. This makes VMs a better choice for running applications that need all the resources and functionalities of a standalone system. VMs are also a better fit for running applications that require different operating systems.


When should I use containers and when should I use virtual machines?

Containers are ideal for applications that can be broken down into microservices, maximizing the number of applications running on a single server. They are also great for creating reproducible development environments.

Virtual machines are useful when you need to run applications that require all the resources and functionalities of a standalone system, or when you need to run different operating systems on the same machine.