This document discusses API testing and answers three common questions about API testing. It first defines what an API is and how it allows software components to interact. It then explains that API testing ensures the functionality of both the API and application code. The three questions answered are: 1) What are the benefits of API testing? 2) How to automate API testing? 3) What are some best practices for API testing? The document provides details on easily testing core functionality, language integration, automation approaches, and best practices like layered architecture and data parsing support.