Eli5: when something is digitally encrypted, how does the receiver get a key to open it without having to send the key with the original information?

Question

Eli5: when something is digitally encrypted, how does the receiver get a key to open it without having to send the key with the original information?

In: Technology

Answer 1

You tell me your **lock** code, but you keep your **unlock** code secret.

Anyone, anywhere, can lock anything using your **lock** code. It is then encrypted and secure. But *only you* can then **unlock** it, because only your **unlock** code will work.

So the **lock** codes can be freely given out and it doesn’t matter, because even with the **lock** code, no one else can **unlock** it.