Semantic HTML plays a crucial role in modern web development by providing meaning to web content, which enhances search engine optimization (SEO), accessibility, and cross-browser compatibility. Unlike non-semantic elements like <div> and <span>, semantic tags such as <header>, <footer>, <article>, and <section> convey the purpose and structure of the content, making it more readable and understandable for both computers and humans. This improves the user experience by allowing assistive technologies to interpret the content accurately, thus aiding visually impaired users and enhancing navigation through screen readers. Additionally, semantic HTML contributes to better SEO by helping search engines understand the hierarchy and importance of the content, thus improving rankings. It also ensures that web pages are accessible across various browsers and devices, which is vital for reaching a wider audience. Tools like LambdaTest provide platforms for cross-browser testing, ensuring that semantic HTML elements function correctly across different environments. By adhering to semantic HTML practices, developers can create more maintainable, efficient, and user-friendly web applications.