Ok one more to add that is a kind-of an abuse of containers: Some compute cluster solutions (like those used for HPC) are using containers to manage software installations on the clusters. They are trying to unify containers with the standard Unix environment, however, so that users still see their home directory (mounted in the container) and other paths so that running applications in the container is the same experience as running it directly on the host OS. This is just a TERRIBLE solution. I much prefer Environment Modules or something like Python's virtual environments (if it worked for arbitrary software installs) as a solution.

https://en.wikipedia.org/wiki/Environment_Modules_(software)