Dictionary.net

One of the instructions, statements or groups ofstatements in a programming language which determines thesequence of execution of other instructions or statements (thecontrol flow).In assembly language this typically consists of jumps andconditional jumps along with procedure call and returnthough some architectures include other constructs such as aninstruction which skips the following instruction depending onsome condition (PDP?), various kinds of loop instructions(later Motorola 680x0) or conditional execution of allinstructions (Advanced RISC Machine).Basic control structures (whatever their names in particularlanguages) include "if CONDITION then EXPRESSION elseEXPRESSION", the switch statement, "while CONDITION doEXPRESSION", "gosub", the suspect "goto" and the much-feared"come from". Other constructs handle errors andexceptions such as traps and interrupts.