Cross-browser compatibility is essential for ensuring that websites and web applications function consistently across different browsers, platforms, and devices. This process, known as cross-browser testing, is crucial for maintaining a positive user experience, as inconsistencies can adversely affect both usability and business outcomes. Developers face challenges due to varying browser capabilities and differing support for HTML, CSS, and JavaScript features, particularly in older browsers or those with smaller market shares. To address these issues, developers can employ strategies such as using CSS resets, vendor-specific CSS implementations, and media queries for responsive design. Additionally, tools like HTML and CSS validators, linters, and browser developer tools can help identify and fix compatibility issues. Despite these efforts, achieving full functionality across all browsers is challenging, making it important to focus on a set of widely used browsers and implement fallback mechanisms for older versions. Services like LambdaTest can assist in testing across diverse environments, offering scalable solutions for comprehensive cross-browser testing.