Webhook

An automated message sent from one app to another when a specific event occurs, a real-time notification that triggers action in another system.

Webhooks enable instant, event-driven automation. Unlike polling (checking repeatedly), webhooks only fire when something happens, faster, cheaper, and more reliable.

When a customer pays on Stripe, Stripe sends a webhook to your system. Your system receives it, marks the order as paid, triggers fulfilment, and sends a confirmation email, instantly.