Related:

• PDP-10: [Programmed Data Processor model 10] n. The machine that made timesharing real.
  It looms large in hacker folklore because of its adoption in the mid-1970s by many university computing facilities and research labs, including the MIT AI Lab, Stanford, and CMU....
• o-op: /noh'op/ alt. NOP /nop/ [no operation] n. 1.
  (also v.) A machine instruction that does nothing (sometimes used in assembler-level programming as filler for data or patch areas, or to overwrite code to be removed in binaries)....
• JRST: /jerst/ [based on the PDP-10 jump instruction] v.
  obs. To suddenly change subjects, with no intention of returning to the previous topic....
• ASCIIbetical order: /as'kee-be'-t*-kl or'dr/ adj.,n.
  Used to indicate that data is sorted in ASCII collated order rather than alphabetical order....
• flag day: n. A software change that is neither forward- nor backward-compatible, and which is costly to make and costly to reverse.
  Can we install that without causing a flag day for all users?...
• flag: n. A variable or quantity that can take on one of two value
  a bit, particularly one that is used to indicate one of two outcomes or is used to control which of two things is to be done....
• bum: 1. vt. To make highly efficient, either in time or space, often at the expense of clarity.
  I managed to bum three more instructions out of that code....
• DPB: /d*-pib'/ [from the PDP-10 instruction set] vt.
  To plop something down in the middle. Usage: silly....
• mode bit: n. A {flag}, usually in hardware, that selects between two (usually quite different) modes of operation.
  The connotations are different from {flag} bit in that mode bits are mainly written during a boot or set-up phase, are seldom explicitly read, and seldom change over the lifetime of an ordinary program....