Webhooks are automated messages sent from apps when something happens, allowing them to share real-time data with each other. They are faster and require less work than polling, working similarly to SMS notifications. To use webhooks, you need to know how to send data to a unique URL, which is typically secured through obscurity or encryption. Webhooks can connect two apps, enabling automated messaging and data sharing between them. They are similar to APIs but simpler, with one-to-one connections that run automatically. By testing webhooks and serializing data, you can make software do whatever you want, using tools like RequestBin and Postman to experiment and learn. Once set up, webhooks can be used in any app with Zapier, enabling automated workflows and integrations between apps.