A webhook is a user-defined HTTP callback. It is a mechanism that sends real-time information to any third-party app or service. As a result, it becomes easy to keep your application in sync with your Contentstack account.
Webhooks allow you to specify a URL to which you would like Contentstack to post data when an event happens. So, for instance, if you want to be notified every time a new entry is created in a content type, you can create a webhook for it. You can add webhooks for almost all the events in Contentstack.