A webhook (also known as a web callback or HTTP push API) is a mechanism for a program to provide real-time data to other apps. A webhook sends data to other applications in real time, so you get it right away. Unlike traditional APIs, you won’t have to poll for data very often to receive real-time results. Webhooks become significantly more efficient for both the provider and the consumer because of this.
Webhooks are sometimes referred to as reverse APIs, however they allow you to skip a step. Most APIs provide a request and a response. A webhook does not require a request; it just provides the data when it is ready.
To use a webhook, you must first register a URL with the service provider. That URL points to a location in your application where the data will be accepted and processed. Under some cases, you can specify the circumstances in which you’d like to get data from the source. The webhook will transmit fresh content to your URL as it becomes available. However, the sole disadvantage of webhooks is the complexity in putting them up at first.