counted loops just be sure to use an identifier that you are not using for any other purpose otherwise you might accidentally wipe out value that you will need later the interesting and useful thing about loops is the way that they alter the "flow of controlin program usually we think of computers as executing series of instructions in strict sequence introducing loop causes python to go back and do some statements over and over again statements like the for loop are called control structures because they control the execution of other parts of the program some programmers find it helpful to think of control structures in terms of pictures called flowcharts flowchart is diagram that uses boxes to represent different parts of program and arrows between the boxes to show the sequence of events when the program is running figure depicts the semantics of the for loop as flowchart more items in no yes next item figure flowchart of for loop if you are having trouble understanding the for loopyou might find it useful to study the flowchart the diamond shaped box in the flowchart represents decision in the program when python gets to the loop headingit checks to see if there are any (moreitems left in the sequence if the answer is yesthe loop index variable is assigned the next item in the sequenceand then the loop body is executed once the body is completethe program goes back to the loop heading and checks for another value in the sequence the loop quits when there are no more itemsand the program moves on to the statements that come after the loop