API Testing

API testing is a type of software testing that involves directly interacting with an application's Application Programming Interface (API) to evaluate its performance, functionality, reliability, and security. Unlike traditional GUI testing which focuses on user-facing elements of an application, API testing is concerned with the business logic layer of the software architecture. This testing verifies that the API returns the expected responses for a given set of inputs, handles error conditions correctly, and behaves as expected under various conditions. It can include testing various aspects of the API such as the HTTP response codes, response times, data accuracy, authorization checks, and error codes. API testing can be conducted manually using tools like Postman or automatically with various programming languages and frameworks.