What is a `defaults write` command?
macOS stores user preferences and application settings in plist (property list) files. While many of these settings are available in the System Settings UI, hundreds of powerful features and tweaks remain completely hidden.
The defaults write command is a Terminal utility that allows you to directly edit these hidden settings. By running a specific command, you can change macOS behavior, speed up animations, or customize the Dock in ways Apple doesn't expose in the standard interface.
Are these commands safe?
Yes. These commands are simply modifying standard macOS preferences. You can always revert a change by either deleting the preference using defaults delete, or by changing the value back to its original state using our tool.
Why do I need to restart Finder or Dock?
When you change a setting using defaults write, the application (like Finder or Dock) doesn't automatically know that the underlying file has changed. By running killall Finder, you force the app to restart and immediately reload the new preferences.