Flowchart - Basic Symbols used in Flowchart - Flowchart with Example

Flowchart:

• Flowchart is a graphical representation of an algorithm.
• Programmers often use it as a program-planning tool to solve a problem.
• It makes use of symbols which are connected among them to indicate the flow of information and processing.
• It shows logic of an algorithm
• It emphasizes individual steps and their interconnections

Basic Symbols used in Flowchart:

Terminal:

• The oval symbol indicates Start, Stop and Halt in a program’s logic flow. 
• Terminal is the first and last symbols in the flowchart

Input/Output:

• A parallelogram denotes any function of input/output type.
• Program instructions that take input from input devices and display output on output devices are indicated with parallelogram in a flowchart. 

Processing/Rectangle:

• A box represents arithmetic instructions.
• All arithmetic processes such as adding, subtracting, multiplication and division are indicated by action or process symbol. 

Decision:

• Diamond symbol represents a decision(or branch) point.
• Decision based operations such as yes/no question or true/false are indicated by diamond in flowchart.
• The program should continue along one of the two routes.(r.g IF/THEN/ELSE) 

Connectors:

• Whenever flowchart becomes complex or it spreads over more than one page, it is useful to use connectors to avoid any confusions.
• It is represented by a circle.

Flow lines:

• Flow lines indicate the exact sequence in which instructions are executed.
• Arrows represent the direction of flow of control and relationship among different symbols of flowchart. 

Example:

• Draw a flowchart for a program that determine if the temperature degree is above or below freezing.

Input

• Temp.

Processing

• Check if Temp is below the 32 ==> below freezing.
• Check if Temp is above the 32 ==> above freezing. 

Output

• Print “below freezing” or “above freezing”