A well-designed RESTful API is a crucial component of any modern web application or service, providing a standardized way for clients to access and manipulate data. In this tutorial, we covered the broad steps taken to expose an internal application using a REST API, including defining the API's intended purpose, identifying resources, defining message format, determining endpoints, implementing endpoints, documenting your API, and publishing your API. We also discussed the importance of understanding RESTful APIs, including the Representational State Transfer (REST) architectural pattern, HTTP methods, and JSON schema. Additionally, we touched on the importance of proper documentation and publishing an API to make it more accessible to developers who can use it to build client applications.