Lazy loading defers image loading until they enter the viewport, dramatically improving initial page load times and reducing bandwidth consumption for users. As the creator of CoreUI, a widely used open-source UI library, I’ve implemented lazy loading in media-heavy applications. The most efficient approach is combining native HTML loading=‘lazy’ attribute with Intersection Observer API for browsers that need polyfill support. This method provides optimal performance, progressive enhancement, and graceful degradation across different browser capabilities.