Cross browser testing involves ensuring a web application performs consistently across various browsers, requiring strategic planning and execution to efficiently manage time and resources. The process is likened to introducing a new dish in a restaurant, progressing through three levels: initial development, controlled testing, and full-scale release. Initially, developers test their application for bugs on local browsers, followed by strategizing tests across different browsers while prioritizing high-risk browsers to minimize iterations. The final level involves sanity testing, focusing on the most popular browsers among the target audience. This approach helps in achieving optimal performance with minimal efforts, ensuring a seamless user experience across platforms. Data analysis tools like Google Analytics can assist in identifying the most used browsers, enabling more targeted testing.