Structure charts

Structure charts can map the structure and data flow of complicated tasks

A Structure Chart in software engineering is a chart which shows the breakdown of a system to its lowest manageable parts. They are used in structured programming to arrange program modules into a tree. Each module is represented by a box, which contains the module's name. The tree structure visualizes the relationships between modules, showing data transfer between modules using arrows. 

Symbol	Name	Meaning
Module Name	Process	Each Box represents a programming module, this might be something that calculates the average of some figures, or prints out some pay slips
	Data Couple	Data being passed from module to module that needs to be processed.
	Flag	[Extension - you don't need to know this for the exam] Check data sent to process to stop or start processes. For example when the End of a File that is being read is reached, or a flag to say whether data sent was in the correct format

Let's take a look at a simple example of how this might be executed when representing the following code:

dim num1 as integer
dim num2 as integer
 
sub calculateAverage()
  dim avg as integer
  inputNums()
  avg = average(num1, num2)
  outputAvg(avg)
end sub
 
function average(a,b)
  return (a + b) / 2
end function
 
sub inputNums()
  num1 = console.readline()
  num2 = console.readline()
end sub
 
sub outputAvg(x)
  console.writeline("average = " & x)
end sub