JUnit Jupiter, part of JUnit 5, is an advanced testing framework designed to support Java 8 and newer versions, integrating the functionalities of JUnit 4 with new capabilities to enhance unit testing. JUnit 5 is modular, comprising JUnit Platform for test execution, JUnit Jupiter for writing tests, and JUnit Vintage for backward compatibility with older versions. It introduces annotations like @Test, @RepeatedTest, and @ParameterizedTest for efficient test structuring and execution while supporting the creation of composed annotations. The framework allows running tests with specific tags and provides capabilities for repeated and parameterized tests. Additionally, JUnit tests can be executed on platforms like LambdaTest, offering cloud-based automation with support for cross-browser testing. The article outlines practical examples and code snippets for setting up and running tests using Maven dependencies, emphasizing the use of Selenium for browser automation and LambdaTest's cloud capabilities for scalable testing solutions. The guide concludes with a brief overview of JUnit Jupiter's role in the JUnit 5 ecosystem, enhancing testing strategies for developers.