[1] Algebraic Operation Systematic - Operationsnotation: Operator1 Operand Operator2 = Ergebnis; Gegenteil: UPN

[2] Academic Operating System

[3] Alternate Operator Service {Telefonie}

[4] Add One and do not Skip - PDP-10-Assembler-Statement

[5] Advanced Operating System (Data General)

[6] Amook, AK, USA -internationale Fughafen-Kennung.