Flow Charting

A flowchart is a formalized graphic representation of a program logic sequence, work or manufacturing process, organization chart, or similar formalized structure. In computer programming, flowcharts were formerly used to describe each processing path in a program, (the main program and various subroutines that could be branched to). Programmers were admonished to always flowchart their logic rather than carry it in their heads. With the advent of object-oriented programming and visual development tools, the traditional program flowchart is much less frequently seen. However, there are new flowcharts that can be used for the data or class modeling that is used in object-oriented programming.

Traditional program flowcharting involves the use of simple geometric symbols to represent a process (a rectangle), a decision (a diamond), or an I/O process (a symbol looking something like the home plate in baseball). These symbols are defined in ANSI x 3.5 and ISO 1028.

Flowcharting Symbols

There are 6 basic symbols commonly used in flowcharting of assembly language programs:

1. Terminal
2. Process
3. Input/Output
4. Decision
5. Connector
6. Predefined Process

This is not a complete list of all the possible flowcharting symbols, it is the ones used most often in the structure of programming.

Symbol	Name	Function
	Process	Indicates any type of internal operation inside the Processor or Memory (STORE INFORMATION & DO CALCULATIONS -variables)
	Input/Output	Used for any Input or Output operation. .
	Decision	Used to ask a question that can be answered in a binary format (Yes/No, True/False)
	Connector	Allows the flowchart to be drawn without intersecting lines or without a reverse flow.
	Predefined Process	Used to invoke a subroutine or an interrupt program.
	Terminal	Indicates the starting or ending of the program, process, or interrupt program.

General Rules for flowcharting

1. All boxes of the flowchart are connected with Arrows. (Not lines)
2. Flowchart symbols have an entry point on the top of the symbol with no other entry points.
3. The exit point for all flowchart symbols is on the bottom except for the Decision symbol. The Decision symbol has two exit points; these can be on the sides or the bottom and one side.
4. Generally a flowchart will flow from top to bottom.
5. Connectors are used to connect breaks in the flowchart. Examples are:
   • From one page to another page.
   • From the bottom of the page to the top of the same page.
6. Subroutines have their own and independent flowcharts.
7. All flow charts start with a Terminal or Predefined Process symbol.
8. All flowcharts end with a terminal.