Docker

Copies files and folders between a container and the host, in either direction. Works on stopped containers too.

Runs a command inside an already-running container — the way in when you need to poke around live.

Shows the full low-level JSON for a container, image, volume or network: IP address, mounts, env vars, exit code, health and more.

Prints a container's stdout/stderr — the first place to look when a container is crashing or misbehaving.

Lists containers — running ones by default, everything with -a. The first thing to check when "it's not working".

Creates and starts a new container from an image — the everyday entry point for running anything in Docker.

Manage the lifecycle of existing containers: stop and start them without losing their state, restart them, or remove them for good.

Live CPU, memory, network and disk usage per container, and the processes running inside one: the quick way to find the container hogging resources.