What is the cloud?

You ask: What is cloud?

No, cloud not up in sky with rain. "Cloud" is trick name for other tribe's computers. Big companies build huge caves — data centers — full of thousand thousand humming machines, rows like sleeping mammoth herd. When Caveman save picture "to cloud", picture travel down wires and radio waves to one of those far machines, and sit on its disk. Real disk, real cave, real place — and big cloud tribes keep at least three copies in three separate caves, so if one cave flood, picture safe in other cave. Want picture back? Phone ask over internet, far machine send copy back quick. Feel like picture float everywhere; really it just stored somewhere else and fetched fast. Caveman pay rent for shelf space in stranger's cave. Cave wisdom: cloud just other tribe's computer. Caveman stuff not in sky — Caveman stuff on someone else's rock, behind someone else's door.