

Glocks have some internal safety mechanisms which make them drop-safe, and which makes it basically impossible for them to go off without fully pulling the trigger, but they don’t have a manual safety that you’d flip on and off with your thumb or whatever. The main point of a traditional manual safety is to keep the gun from firing while you’re carrying it, like if you were walking through the woods and a stray branch or something pokes your holster hard enough to move the trigger, for example, the safety would prevent the gun from firing. Or on some pistols (but definitely not all pistols), the manual safety will keep it from firing if you drop it. But with pistols like Glocks which are already drop-safe, modern hard-sided Kydex holsters have made a manual safety kind of redundant because they’re molded to the exact shape of the gun and they completely enclose the trigger guard to keep out anything that might accidentally move the trigger. It’s sort of like having a hard case for your gun right on your hip. So if you’re going to carry a pistol which doesn’t have a manual safety, Kydex holsters are pretty much the only way to go.
As for manual safeties being required by law, they definitely aren’t where I live. I’ve don’t recall ever seeing a Glock with a safety. But gun laws vary a lot from state to state. If you live somewhere like California it wouldn’t surprise me if a law like that existed there, but I doubt it would most other places.

I think I would have been a lot happier if I’d never learned that.