---
sidebar_label: EventEmitter.on
# EventEmitter.on() method
Bind an event listener to fire when an event occurs.
#### Signature:
```typescript
class EventEmitter {
on(event: EventType, handler: Handler<any>): this;
}
```
## Parameters
| Parameter | Type | Description |
| --------- | -------------------------------------------- | ------------------------------------------------------------------ |
| event | [EventType](./puppeteer.eventtype.md) | the event type you'd like to listen to. Can be a string or symbol. |
| handler | [Handler](./puppeteer.handler.md)<any> | the function to be called when the event occurs. |
**Returns:**
this
`this` to enable you to chain method calls.
