Plain definition: A webhook is a way for one app to instantly notify another app when something happens. Instead of one system repeatedly asking “did anything change?”, the first system pushes a message the moment an event occurs.

In plain terms

Imagine two ways your package could be tracked. Option one: you refresh the tracking page every ten minutes hoping for an update. Option two: the shipping company texts you the moment your package moves. Webhooks are option two — the app sends you a notification the instant something happens, rather than you constantly checking.

Why it matters for operators

Webhooks make automations fast and efficient. When your e-commerce platform fires a webhook the moment an order is placed, your fulfillment system, inventory tracker, and accounting tool can all react within seconds. Without webhooks, systems have to poll for updates on a schedule, which means delays and wasted resources. Most automation tools like Make and Zapier use webhooks under the hood.

Example

A personal trainer uses a booking app that fires a webhook whenever a client cancels. That webhook triggers an automation that immediately opens the time slot, updates the trainer’s calendar, and sends a waitlist client an offer to book — all within seconds of the cancellation.