Cross-platform testing is a software testing technique used to ensure the functionality and compatibility of an application across different operating systems, devices, and browsers. This type of testing is essential in today's digital landscape where users access applications on a variety of platforms, such as desktop computers, mobile devices, and tablets. By conducting cross-platform testing, software testers can identify and resolve any issues related to the application's performance, usability, and responsiveness on various platforms, thereby providing a seamless user experience. Automated tools are often used in cross-platform testing to streamline the testing process and improve efficiency.