Explore website caching techniques in this 23-minute conference talk from DrupalCon Lille 2023. Dive into the necessity of caching for online shopping, Core Web Vitals, and high-latency internet scenarios. Gain insights into multiple caching layers, from browser cache and HTTP headers to server-side in-memory object cache with Drupal modules and content delivery networks. Learn to troubleshoot stale content, understand Drupal's caching strategies, and differentiate between various cache layers involved in web requests. Suitable for developers, Drupal site administrators, and DevOps professionals, this talk provides both basic and advanced caching concepts to enhance website performance and user experience.