Progressive enhancement is a web development strategy that prioritizes content accessibility across all devices and browsers by building a basic functional experience, then adding advanced features for browsers that support them. This approach ensures broader accessibility and usability by focusing initially on clean, semantic HTML for structure, followed by CSS for presentation enhancements, and finally JavaScript for additional functionality. Unlike graceful degradation, which starts with advanced features for modern browsers and scales back for older ones, progressive enhancement prioritizes universal access and performance, improving loading times and accessibility. Techniques like avoiding inline styling, using unobtrusive JavaScript, preloading fonts, implementing responsive design, lazy loading images, and utilizing feature detection are recommended to ensure websites are adaptable, scalable, and efficient. This methodology aligns with the core principles of the web to be universally expressive and accessible, facilitating a stable application experience across diverse platforms.