What Is an Event in Programming: Meaning & Examples

In programming, an event is something that happens and triggers code to run — such as a mouse click, a key press, or a tap on the screen. Unlike the everyday meaning of "event" (an occasion or gathering), an event in coding is a signal that tells the program when to react. The program waits for an event to happen, then runs the instructions prepared to respond to it.

Table of Contents

• How an Event Works
• Types of Events
• Why It Matters for Kids

How an Event Works

Every event is linked to a block of code called an "event handler" — code that runs only when that event happens. The program keeps waiting; the moment the user does something, the event fires and the code runs at once. In Scratch this is easy to see: the "when green flag clicked" block runs everything below it as soon as the flag is pressed. There are also blocks like "when space key pressed" or "when this sprite clicked". In Python, an event might be input() waiting for the user to type. A real example: in a game, a character does not jump on its own — it jumps because a "space key pressed" event triggers the jump code. In fact, almost every app you use — from games to the "send" button in a chat app — works based on events.

Types of Events

Events are grouped by what triggers them. The most common kinds:

• Mouse events: a click, a double-click, or moving the cursor.
• Keyboard events: pressing or releasing a key.
• Touch events: tapping or swiping the screen on a phone or tablet.
• Timer events: triggered automatically after a set delay, such as spawning an enemy every 5 seconds in a game.

A style of coding where the whole flow is driven by events like these is called event-driven programming, and almost every modern app uses it. A child can build their first event-driven game in a free Algonova coding class.

Why It Matters for Kids

Understanding events teaches kids to think in cause and effect: "if this happens, then do that." It is the foundation of building interactive programs that respond to the user, instead of just running by themselves. In the Algonova coding course, kids learn events through games they build themselves, and the concept is closely tied to what a variable is, which stores the result of each action.

Want your child to build their first game that reacts when a button is pressed? Try a free Algonova coding class.