Actually Existing Socialism, a term coined during the Brezhnev era in the USSR (and used sarcastically nowadays to mock leftists and, more specifically, tankies) to refer to the 'real socialism' achieved by the Eastern Bloc countries (or whatever country in specific they like the most) in contrast to their various opponents in the left, regardless of whether or not their economy matched socialist theory.
1) The process in which the U.S. government (NIST) approves a cryptographic standard.
2) The winner of the latest U.S. government cryptographic testing. In this case, Rijndael won. It's a block cipher with a 128-bit block size. It uses a 128-bit, 192-bit or 256-bit key size and is considered to be extremely secure.
The Serpent cipher came a close second to Rijndael in the AES competition.
When you say good-bye to someone and then realize you're walking in the samedirection so you start walking very slowly and hope they walk faster. That's an instance of obvious AES (awkward ending syndrome).