Cryptology splits into two complementary disciplines — what are they, and what does each one do?

Cryptography builds the protection (encryption); cryptanalysis tries to break it (extracting information from ciphertext).

* Cryptology splits into building protection (cryptography) and breaking it (cryptanalysis); cryptography further splits into symmetric and asymmetric. *

Kryptologie (cryptology) is the umbrella term, divided into:

The two are in a permanent arms race: cryptographers design schemes, cryptanalysts attack them, and schemes that survive sustained cryptanalysis are the ones we trust.

Tip: "-grafie" = writing (building secrets), "-analyse" = breaking (taking them apart). Both together = cryptology.

Go deeper:

• Cryptanalysis (Wikipedia) — the "breaking" half of cryptology, from Enigma to modern side-channel attacks.