The world has a lot of different standards for a lot of things, but I have never heard of a place with the default screw thread direction being opposite.
So does each language have a fun mnemonic?
Photo credit: https://3.bp.blogspot.com/-Giy8OrYJTjw/Tfm9Ne5o5hI/AAAAAAAAAB4/c7uBLwjkl9c/s1600/scan0002.jpg
One mnemonic is to imagine yourself opening a jar.
Your door is a jar.
Is it a jar of jam or jelly?
I use the right hand rule - ball up your fist with your thumb sticking out, and turning in the direction of your fingers curling will result in the screw going the rest your thumb points.
Me learning this about electromagnetism: huh, neat.
Me learning this about something I actually use in day to day life: 🤯
It’s especially helpful when you’re looking at screws (or nuts!) from the back or any other weird frame of reference.
Right hand for right-handed threads and left hand for left-handed. If unsure, it’s most likely right-handed.
The assumption in this whole post is that it’s right-thread, since left is so uncommon.