What type of testing focuses on the app's performance under both normal and extreme conditions?

Performance testing is specifically designed to evaluate how an application operates under a variety of conditions, including both typical and extreme loads. This type of testing assesses the speed, scalability, and reliability of the application by simulating different user behaviors and measuring response times, resource usage, and overall system stability.

During performance testing, the application is subjected to stress to identify the breaking points and ensure that it can handle expected volumes of traffic and data. This testing is crucial for determining whether the application can maintain acceptable performance levels when facing high usage scenarios or when system resources are constrained, which is essential for ensuring a good user experience and system reliability in real-world applications.

Functionality testing focuses solely on verifying that the application functions according to specified requirements. Unit testing checks individual components for correctness, while security testing aims to identify vulnerabilities within the application. While all these testing types are important in the software development lifecycle, only performance testing specifically addresses the application's behavior under varying loads and extreme conditions.