Chapter 1: The importance of site performanceWhy is Site Speed So Important2 minsWhat This Course Covers2 minsWhat You Should Know2 minsCommon Terms4 minsChapter 2: Site content optimizationImage & Media Optimization5 minsWhat is Lazy Loading and How Does It Work?4 minsWhat are Render-Blocking Assets?4 minsRemoving Missing Files3 minsPractical Application: Speeding Up WordPress16 minsChapter 3: Caching and CDNsWhat is Cache and How Does It Work?4 minsCaching Pitfalls4 minsUsing a CDN4 minsPreventing Mixed Content Errors4 minsChapter 4: Coding practices for a strong foundationGood Coding Practices4 minsWriting Critical CSS5 minsJavaScript Best Practices5 minsLazy Loading, Async, Defer4 minsOn Database Queries5 minsChapter 5: Speed tests and performance trackingWhat Are You Testing For?3 minsDoing Speed Tests5 minsUsing Chrome Developer Tools3 minsActual Device Testing4 minsUsability Testing3 minsChapter 6: Next StepsNext Steps1 min Play videoPreviousNextTraversing the DOM can put stress on a browser and make a site slower. Here are some tips for working with the DOM, as well as how async and defer work.