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Operating System Shortcuts

Operating system shortcuts sit underneath every other application on this site, and they're arguably the highest-leverage shortcuts to learn precisely because they apply constantly regardless of which specific program you happen to have open — window snapping, virtual desktop switching, and screenshot capture are used dozens of times a day by nearly everyone, in a way that even the deepest application-specific shortcut set can't match for sheer frequency.

Because OS-level shortcuts apply globally rather than being scoped to one application, they're also the ones most likely to conflict with an application's own shortcut for the same key combination — worth keeping in mind when a shortcut that should work inside a specific app instead triggers a system-level action, which usually means the OS has claimed that combination first before the application ever sees the keypress.