JMeter: Open-Source Load & Performance Testing Tool

JMeter is an open-source software that is used for load testing, performance testing, and functional testing of web applications. It can simulate a large number of users accessing a website or application, allowing developers to identify performance issues and optimize their application to handle high volumes of traffic. JMeter can also be used for functional testing, where it can simulate user behavior and validate that the application is functioning as expected. It supports various protocols like HTTP, HTTPS, FTP, JDBC, SOAP, and more. JMeter is written in Java and can be run on any platform that supports Java.