Many of your daily computer activities — like opening programs, logging onto email, and navigating websites — are saved as temporary files within your computer. This is called caching, which, as Apple puts it, “helps reduce internet data usage and speed up software installation on Mac computers, iOS and iPadOS devices, and Apple TV.”
When you visit a website, for example, your browser will download data like images, scripts, and login credentials and save it all in a cached folder. When you visit that same site in the future, your browser simply (and quickly) loads data from the folder it's already created. That way, your computer doesn’t have to spend time downloading all of that information again — it can just pull it from the cache. Read more...
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