Webhooks are used to send messages or payloads from one application to another after a specific operation executes, facilitating communication between services. This text describes the process of building a Todo API using Flask, with the integration of Convoy to publish webhook events for operations like creating, updating, and deleting Todo items. It outlines the setup and configuration of the API, including the necessary prerequisites such as a Convoy Cloud account and API key, and explains how to define and handle events like "created," "updated," and "deleted." The text provides step-by-step instructions for setting up the environment, creating endpoints, and sending webhook events, emphasizing the use of Convoy to ensure reliable event publishing. It also touches on best practices for production environments, such as scoping endpoints to users and publishing webhooks from workers rather than controllers.