What is an API?

An API is essentially a contract between two software applications. It specifies how software components should interact, what data they can request, and what actions they can perform. APIs enable the integration of different software systems, allowing them to work together seamlessly. APIs let developers use certain features or get data from a service without needing to know how that service works inside.

APIs have the following components:

• Endpoints: Specific URLs or URIs that an API exposes for different functionalities.
• Request methods: HTTP methods such as GET, POST, PUT, DELETE, and others. These are used to perform different actions on the resources.
• Request and response formats: APIs define how data should be structured when it’s sent to the API (request) and how the API will structure its response.

Let’s imagine an API for a book catalog, and discuss the aforementioned components for it. In this API, we might have different...