Simply put, Webhooks are ways for your online accounts to "speak" to one another and get notified automatically when something new happens. You'll need to know how to use webhooks if you want to automatically push data from one app to another.
Webhooks always use the POST API Verb since the other services are "Sending/Posting Data" to your Webhook endpoint. In order to receive the response from a webhook, the very first function in your Function stack should be Get All Input as shown below.
You can use the Request History to see the response of a Webhook. This is important to do because it will help you create the logic in your function stack based on the data being sent. You can see how to access the Request History to view the response of a Webhook in the tutorial below.