What is Docker primarily used for?

Docker is primarily used for the containerization of applications. This technology enables developers to package applications and their dependencies into standardized units called containers. Each container isolates the environment in which an application runs, ensuring consistency across different environments, such as development, testing, and production. By using containers, developers can eliminate many of the traditional issues that arise with software deployment, such as environment discrepancies and dependency conflicts.

Containerization provides many advantages, including resource efficiency, quick scalability, and the ability to deploy applications on various platforms without modification. Docker's focus on creating lightweight, isolated containers makes it distinct from traditional virtual machines, which virtualize entire operating systems and are less efficient in terms of resource usage.

While the other options touch on relevant topics, they do not capture Docker's primary purpose. Virtualizing operating systems is related to traditional virtualization solutions, and managing databases or configuring network settings are more specialized tasks that can be associated with containers but do not define Docker's core function.