Lesson 1 of 12

What Are Flowcharts?

Have you ever followed a recipe, or used a map to navigate somewhere? If so, you've already used something very similar to a flowchart. A flowchart is a visual diagram that shows the steps of a process, connected by arrows that show the order things happen.

Why do programmers use flowcharts? Before writing code, it helps to plan out the logic step by step. Flowcharts let you see how a program works, making it easier to spot mistakes and understand complex logic.

The Four Basic Shapes

Every flowchart uses a small set of standard shapes. Each shape has a specific meaning. Let's learn the four most important ones.

Start / End

Terminal

Rounded oval shape. Marks the start or end of a flowchart. Every flowchart begins and ends with one of these.

Do something

Process

Rectangle. Represents an action or step — something the program does, like a calculation or assignment.

Yes or No?

Decision

Diamond shape. Asks a question with a Yes/No (True/False) answer. The flow splits into two paths based on the answer.

Input/Output

Input / Output

Parallelogram. Represents getting data in (like asking the user a question) or showing data out (like displaying a result).

Arrows Show the Flow

Shapes are connected by arrows (also called flow lines). Arrows show the order in which steps happen. You read a flowchart by following the arrows, usually from top to bottom.

Key rule: A flowchart always has exactly one Start and at least one End. You follow the arrows from Start, through all the steps, until you reach End.

Your First Flowchart

Here's a simple flowchart that shows the steps of making a cup of tea. Click Next to step through it one step at a time.

Start Boil water Put tea bag in cup Pour water into cup Wait 3 minutes Remove tea bag End

Notice how every step is inside a shape, and arrows connect them in order. The flowchart reads from top to bottom — just like a recipe!

Key Takeaways

  • Flowcharts are visual diagrams that show the steps of a process in order.
  • There are four basic shapes: Terminal (oval), Process (rectangle), Decision (diamond), and Input/Output (parallelogram).
  • Arrows connect shapes and show the direction of flow (usually top to bottom).
  • Every flowchart has a Start and an End.