System Design · Junior · Question 69 of 75

What is a webhook?

✓Correct answer: An HTTP request a service sends to your URL when an event happens (e.g. payment succeeded)
2A React hook for the web
3A browser API for notifications

Explanation

It's the reverse of polling: the provider pushes events. The receiving endpoint must verify signatures and handle retries.

Further reading

Wikipedia: Webhook ↗

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