The properties or features of an object which help users understand it's function. A chair, for example, affords the abilty to be sat on.
Cumulative Layout Shift (CLS)
This measures how much a page’s content shifts and jumps around as the page loads. Part of Google's Core Web Vitals.
First Input Delay (FID)
Measures how quickly a user can interact with a page — say clicking a link or button. Part of Google's Core Web Vitals.
Largest Contentful Paint (LCP)
Largest Contentful Paint measures how quickly the largest, above-the-fold element on a page loads. Part of Google's Core Web Vitals.