[sacnoradhq]

Dan Boneh's intro cryptography course is excellent.[0] The closest to a Khan Academy "cryptography edition" one can find.

0. https://www.coursera.org/learn/crypto

PS: I must be old because I can't get past the neologism of "crypto" abused to mean "cryptocurrency" rather than "cryptography."

[remcob]

I started reading the ‘crypto’ in cryptocurrency as in cryptozoology. It makes more sense that way.

[joe__f]

That's like, the study of concealed animals?

[Icathian]

Mythological animals. But I am now going to think of camouflaged unicorns for a while.