A flowchart is a way of visually representing the flow of data through an information processing system, the operations performed within the system, and the sequence in which they are performed. A program flowchart describes the sequence of operations required to solve a given problem. A programmer will often create a flowchart before writing a program.

The flowchart is drawn according to defined rules, using standard flowchart symbols. Flowcharts help us to understand the logic of complex problems, and make it easier to write programs in a high level programming language. Some commonly used flowcharting symbols are shown below.

Flowcharts are a good way of communicating the logic of a system to others, and allow problems to be analysed effectively. They can also form part of the program's documentation, and are useful for facilitating efficient coding and debugging. Flowcharts can, however, become complex and unwieldy if the program in question is large and complex. They may also need to be completely redrawn if changes are required, depending on how they have been produced.

ANSI Flowchart Symbols
Flowchart flowline symbol Flowline Lines that connect other flowchhart symbols and indicate the direction of logic
Flowchart terminal symbol Terminal Indicates the start or end of a task
Flowchart input/output symbol Processing Arithmetic or data-manipulation operations
Flowchart  symbol Input/Output Indicates an input or output operation
Flowchart decision symbol Decision Decision making and branching
Flowchart connector symbol Connector Used to join different parts of a program
Flowchart offpage symbol Offpage Indicates that the flowchart continues on another page.
Flowchart predefined symbol Predefined Represents a group of statements that perform some processing task
Flowchart annotation symbol Annotation Provides additional information about another flowchart symbol

Flowchart guidelines

An example flowchart - a progam to compute the factorial of N

An example flowchart

An example flowchart