Speculative loading and the Speculation Rules API

Speculative loading, or navigation speculation, is the concept of predicting (speculating about) which page a user might visit next and doing some or all of the work to load that page before they visit it. This way, if the user does end up navigating to the page, it appears to load much faster. Browsers have offered several types of resource hints to enable speculation for many years, but many of these interfaces have been clunky and inflexible to use. Google has recently introduced the Speculation Rules API in Chromium, designed to make it easier to prefetch and prerender documents for future navigations.

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