Integration Testing
Integration testing is a software testing methodology that focuses on verifying the interactions and data flow between integrated components or modules of an application. It ensures that combined units work together as expected, detecting interface defects, data mismatches, and communication errors that unit testing might miss. This testing level typically occurs after unit testing and before system testing in the software development lifecycle.
Developers should learn integration testing to validate that different parts of their application (e.g., APIs, databases, microservices) interact correctly, which is crucial for complex systems where components are developed independently. It's essential when building distributed systems, microservices architectures, or applications with third-party integrations to prevent integration failures in production. This methodology helps catch issues early, reducing debugging time and improving software reliability.