performance

Core Web Vitals are Google's metrics for user experience: LCP (loading), INP (interactivity), and CLS (visual stability). They matter because they affect search rankings and directly correlate with user satisfaction and conversion rates.

Optimize images by: using modern formats (WebP, AVIF), proper sizing for display dimensions, lazy loading below-the-fold images, using responsive images with srcset, and compressing without visible quality loss.

Lazy loading defers loading non-critical resources until they're needed. For images, use loading="lazy" attribute. For JavaScript, use dynamic import() or React.lazy(). This reduces initial page load time and saves bandwidth.

Web caching includes browser cache (HTTP headers like Cache-Control), CDN caching for static assets, application cache (localStorage, sessionStorage, IndexedDB), and service worker caching for offline support. Each serves different purposes.

Minification removes unnecessary characters (whitespace, comments) from code to reduce file size. Bundling combines multiple files into fewer files to reduce HTTP requests. Both reduce load times - bundlers like webpack, Vite handle this automatically.