MD5 (message-digest)
It is a historically widely-used but nowadays insecure hash function that produces a 128-bit hash value.
SHA (secure hash algorihtm)
The two latest versions, SHA-2 and SHA-3, are secure hash functions. Their predecessors, SHA-0 and SHA-1, are insecure.
DES
An algorithm to encrypt data, insecure.
AES (Rijndael)
The spiritual successor of DES, secure.
Message Authentication Code (MAC)
Additional encoding that ensures authentity (the sender is who they claim to be) and integrity (the message has not been changed).
RSA (Rivest–Shamir–Adleman)
It is a cryptographical system to encrypt data and digital signatures, using the hardness of factoring two big prime numbers as the core principal.
Diffie-Hellman Key-Exchange
It is a protocol that enables a secure creation of a shared key that will be used for further encrypted data transfer between two parties. The key is not transmitted.
Bearer token
If you have the token, you are authorized and no other proof is necessary.
JWT (JSON Web Token)
A format for a token.