LCP is one of the three Core Web Vitals. The "largest element" is usually a hero image, video poster, or large text block. To improve LCP: optimise images (WebP/AVIF, lazy-load off-screen ones), use a CDN, inline critical CSS, serve content with caching.
LCP — Largest Contentful Paint
LCP — the time until the largest visible element finishes rendering. Target: ≤ 2.5 seconds at the 75th percentile.