Software Testing is the most significant stage in Software Development Life Cycle. The overall aim of any software industry is to provide quality to the end user. To ensure high-quality software it is required to test. Testing ensures all the requirements are met and the software/application is bug-free. As we are aware websites are rapidly increasing day by day and testing needs to be done to ensure if the site is user-friendly to the end user and there are no bugs in the production environment. This paper mainly focuses on Web application testing, types of web application testing and black box testing techniques. There are many testing techniques used to optimize the test cases, this paper mainly explains the most commonly used techniques used for the web application testing.