Moving around

Directories, paths and tab completion.

The essentials

pwd prints where you are, ls lists what is there and cd moves. A path starting with a slash is absolute; anything else is relative to the current directory.

One dot is here, two dots is the parent, and a tilde is your home directory.
Tab completes names, which prevents most typing mistakes.

The filesystem

Everything hangs off a single root, with no drive letters. /home holds users, /etc configuration, /var logs and changing data, and /usr installed software.