What is Docker primarily used for?

Docker is primarily used for the containerization of applications. This process involves encapsulating an application and its dependencies into a standardized unit called a container. Containers ensure that applications run consistently in different environments, regardless of the underlying infrastructure. This eliminates the "it works on my machine" problem that developers often face when deploying applications across multiple systems.

Using containers allows developers to package their applications with everything they need to run—such as libraries, binaries, and configuration files. This leads to improved portability, scalability, and efficiency since containers share the same operating system kernel, which reduces overhead compared to traditional virtual machines.

Containerization with Docker also facilitates easier management of application lifecycles, as containers can be quickly started, stopped, replicated, or destroyed without impacting the system's overall performance. It makes DevOps practices more streamlined and efficient, enhancing continuous integration and delivery processes.

While creating virtual machines, managing cloud services, and developing mobile applications are important aspects of modern IT and software development, they do not represent the primary functionality of Docker, which focuses specifically on application containerization.