Little programs or scripts or automations you’ve created ad-hoc to solve a particular single use case
I have lots of shortcuts i make on my phone and I have one i love that detects when bluetooth accidentally or purposefully disconnects from my speaker and reconnects it and fixes a playback glitch so its back to playing properly
One or two versions before they included it by default, I wrote a Nemo Action to launch the monitor settings dialog in the right click menu when you right click the desktop.