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In computing, a cache, (pronounced cash), is a component that stores a "snapshot" of data at a given state. It does this so that future visits will load faster for the user.

If you have ever, on a first-time visit to a website, waited patiently while the page loads, and then returned to that page a few days later and noticed that it's quite a bit faster, then you have experienced a cache in action.

Caches exist in just about any piece of technology that serves up some kind of data: a web server, a database server, your mobile phone, your browser...all of these things have at least one, and usually multiple, caches in action to help make your experience as quick and pain free as possible.