What are containers?

Containerization is the operating-system-level or application-level virtualization of resources so that applications can run in isolated environments called containers. Each container packages an application together with its configuration files, libraries, and dependencies, which ensures that it behaves the same regardless of where it is deployed. This “build once, run anywhere” property of containers makes them highly portable and consistent.

Another benefit of containerization is isolation and security. Containers run as separate processes with defined boundaries, preventing the contained application from interfering with other applications or the host system (and vice versa). This means that the impact of a compromised container is typically limited to that container, which improves system stability and security. Furthermore, the isolation of applications (with their dependencies) allows applications with conflicting dependencies to be run on the same machine. In this way, the sandboxing of applications both allows and (by default) forces applications to run in isolation from other applications, which proactively prevents conflicts and interference.

Citations

1. “Containerization (Computing).” Wikipedia, 14 Mar. 2022, en.wikipedia.org/wiki/Containerization_(computing). Accessed 25 Jan. 2026.
2. Wikipedia Contributors. “Docker (Software).” Wikipedia, Wikimedia Foundation, 16 Nov. 2019, en.wikipedia.org/wiki/Docker_(software). Accessed 25 Jan. 2026.