All active variables can be seen by running
$HOME- Expands to the path of my home folder.
$PS1- Variable that represents my command prompt line.
$PATH- Special environment variable that contains the command path (list of system directories that the shell searches when trying to locate a command).
- Scripts are run in subshells, and nothing is shared "upwards". That's the difference between running a script and sourcing one. A sourced (imported) script is run in your own script's namespace.
- In shell everything is a string.
- Children never touch parent environment. It can only if it runs as part of the current process (source, function, alias).
- Pipes are used to connect one process's output with another process’s input.
/etc/paths.ddefine paths to add to
$PATHglobally to all users.