Web basics

Webhook

A reverse API call — an external service pushes data to your app when an event happens.

With a normal API you ask for data; with a webhook the service calls *you* the moment something occurs, so you don't have to keep asking 'did it happen yet?'. For example, Stripe hits your webhook URL the instant a payment succeeds, and your code updates the order. The catch for vibe coders: webhooks arrive from outside, so anyone could fake one — you must verify the signing secret the provider sends, or a stranger could tell your app they 'paid' when they didn't.