Flow of control statements allow programs to execute statements in some fashion other than one right after another. Programs with only sequential flow are unable to respond to unusual situations, do anything more than once, or many other interesting things.
There are several kinds of statements that alter the normal flow of control, each of which have their own exhibits. Consider one of the following:
a) Decision statement. Choose one of several alternatives. The most common is the if statement.
b) Looping statements. There are three statements that provide repetitive execution, with several variations.
c) Function calls or Subprogram calls.