TL;DR: You use the cloud every time an app on your screen reaches a program running on someone else’s machines: browser mail, photo backup, Netflix streams out of Amazon data centers, and games rendered on remote servers all follow one arrangement, a thin client on your side and a shared back end on theirs.

Software as a service means the provider’s application runs on their infrastructure and you reach it through a browser; the NIST definition’s own example is web-based email, and Gmail alone has 1.8 billion users.

Netflix has run on Amazon Web Services since a 2008 database corruption stopped its DVD shipments for three days; cloud games go further and render on the server entirely.

Of the 2010s product shelf, Mailchimp, QuickBooks Online, Box, Toggl Track and Evernote are alive; Mozy shut down in 2019 and Outright in 2022, while their categories carried on.

On the phone, you use the cloud through mobile cloud computing: heavy computation moves off the device, paid for in frequent transmissions and…