Glossary/Common Terms

What is this page?

This page is intended to serve as a site-wide reference to common terms/ideas, with links to and from articles that use these terms.

As a note, this page is not alphabetized normally. The terms are organized into categories, and sorted in an order that I believe will allow others to understand later terms better than alphabetization would.


Encryption Key - An encryption key is essentially the "password" when encrypting or decrypting.

Symmetric - Symmetric encryption algorithms are encryption schemes where both the encryption and decryption are done with the same encryption key.

Asymmetric - Asymmetric encryption algorithms are encryption schemes where the encryption is done with one key, and the decryption is done with a separate key.

Diffie-Hellman Key Exchange (DH) - This is a method of swapping encryption keys over an unsecure form of communication.

X.509 - X.509 is a format for public keys (only some asymmetric algorithms use this format).

GPG/PGP - Gnu Privacy Guard/Pretty Good Privacy are asymmetric encryption algorithms that are compatible with each other.

TLS - The modern method of securing HTTPS connections.

SSL - The older, and less secure method of securing HTTPS connections.

CA - A "certificate authority" is a certificate/agency/government/etc that issues certificates (typically X.509 certificates)

Root CA - A Root CA is the highest possible trust CA. This CA has no parents, but is able to generate any number of "Intermediate CAs", that will be trusted through the Root CA essentially saying that the Intermediate CA can be trusted.

Intermediate CA - A CA that has a parent CA.

Seed - A seed is an input value for an algorithm.

PRNG - A Pseudo Random Number Generator, or PRNG, is an algorithm that take a seed, and can generate a seemingly random output based on that seed.