About this interactive
Five lessons tour the operating systems people carry and use every day.
Android is the Linux kernel with a front end built for mobile devices, and many manufacturers put it on their phones. Because its core is Linux, it will even install on a laptop or desktop, mobile-style buttons and all.
Chrome OS is Linux built by Google for Chromebooks: light hardware for light work, with no Windows licence fee in the price. Chromium OS is the free, open-source project behind it, the one developers download.
macOS is Apple's desktop system. Pinned apps sit in the Dock (right-click, Remove from Dock to unpin), Finder is the file manager, the menu bar at the top belongs to whichever app is in front, and the window buttons sit on the left.
iOS on the iPhone and iPadOS on the iPad share their kernel with macOS but rebuild the front end for touch. You find the version under Settings, General, About. The iPad gets more screen but cannot call over the cell towers, even with a data plan; an app such as Google Voice can call over data instead.
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