What is a CustomEvent in Angular, and how is it used?

Short answer: CustomEvent is a native JavaScript event that allows sending custom data. In Angular, used in event emitters to pass data from child to parent components. Angular wraps this with @Output() and EventEmitter.

Example code

@Output() myEvent = new EventEmitter<string>(); this.myEvent.emit('some data');

Real-world example (ShopNest)

ShopNest admin can be built in Angular with modules/components, services for API calls, and reactive forms for product edit.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.