Functions

• Also called modules, subprograms, procedures, routines
• A self-contained collection of steps that solves a problem or subproblem
• Each function should do one thing, but do it well
• Allows for structured programming—organizing communication between modules
• Easier to understand, test and debug
• Concrete step—a step for which the implementation details are fully specified
• Abstract step—a step for which some implementation details remain unspecified
• Functional Cohesion—A property of a function or module in which all concrete steps are directed towards solving just one problem

<type> <function name> (<parameter list>)
{
  <data declarations>
  <executable statements>
}