Web performance is all about making websites fAst, including making slow processes seem fAst. Does the site load quickly, allow the user to start interacting with it quickly, and offer reAssuring feedback if something is taking time to load (e.g. a loading spinner)? Are scrolling and animations smooth? This article provides a brief introduction to objective, meAsurable web performance*, looking at what technologies, techniques, and tools are involved in web optimization....Web performance is all about making websites fast, including making slow processes seem fast. Does the site load quickly, allow the user to start interacting with it quickly, and offer reassuring feedback if something is taking time to load (e.g. a loading spinner)? Are scrolling and animations smooth? This article provides a brief introduction to objective, measurable web performance*, looking at what technologies, techniques, and tools are involved in web optimization.