Comment by estearum

Other symbols don't appear on the keycaps just like there's only an upper or a lowercase letter on each key on your keyboard. Your keyboard also doesn't tell you there's ¶ or ‡ underneath the 7 key!

Layers sound pretty crazy but if you start slow and adapt towards them, they're just amazingly useful.

Putting all your modifier keys on the homerow is probably the most immediately understandable use of layers: https://precondition.github.io/home-row-mods

These let you type every character/key combo without awkward pinky stretches.

A somewhat bespoke layer usecase that I find valuable as a programmer is holding "S" on my left hand sets characters hjkl; to the open-surround characters like ({[<