Definition - What does Prefetching mean?
Prefetching is the loading of a resource before it is required to decrease the time waiting for that resource. Examples include instruction prefetching where a CPU caches data and instruction blocks before they are executed, or a web browser requesting copies of commonly accessed web pages. Prefetching functions often make use of a cache.
Techopedia explains Prefetching
Prefetching allows applications and hardware to maximize performance and minimize wait times by preloading resources that users will need before they request them.
Web browsers employ prefetching by preloading commonly accessed pages. When the user navigates to the page, it loads quickly because the browser is pulling it from the cache. Some browser plugins download all of the pages that have been hyperlinked to attempt to speed up the browser.
Some operating systems, such as Windows, cache files that a program needs on startup to make loading faster.