What is an external system with which useEffect allows syncronisation?

Q: What is an external system with which useEffect allows syncronisation?

A timer managed with setInterval() and clearInterval(). An event subscription using window.addEventListener() and window.removeEventListener(). Connection to network some browser API, or a third-party library, A third-party animation library with an API like animation.start() and animation.reset().

Difficulty: 5/10

useEffect, external synchronization, cleanup

These systems aren’t controlled by React, so they are called external. An Effect lets you keep your component synchronized with some external system. such as:

1
A timer managed with setInterval() and clearInterval().
2
An event subscription using window.addEventListener() and window.removeEventListener().
3
Connection to network
4
some browser API, or
5
a third-party library, A third-party animation library with an API like animation.start() and animation.reset().

Scenario Questions

0-2 years experience

Follow-up Questions