/mdn2/en-US/docs/Learn/PerformancePerformance
business_case_for_performance CSS HTML JavaScript Measuring_performance Multimedia Perceived_performance video Web_Performance_Basics What_is_web_performance why_web_performance
/mdn2/en-US/docs/Learn/Performance/Measuring_performanceMeasuring_performance
/mdn2/en-US/docs/Learn/Performance/MultimediaMultimedia