CmdZ

CmdZ is the keyboard shortcut for performing Undo on macOS and in many Mac applications. It is activated by pressing the Command key (⌘) together with the letter Z. The command is widely supported across software such as text editors, graphic design tools, IDEs, and office suites, making it a standard part of the macOS user experience.

How it works: When CmdZ is pressed, the application invokes its undo manager to revert the most recent reversible action. Pressing the combination repeatedly steps backward through the action history. The extent of the undo history is defined by the application and may be cleared by certain operations (for example, after saving or closing a document).

Redo alternative: In most macOS applications, the redo action can be triggered with Cmd+Shift+Z. Some apps use Cmd+Y instead. Redo re-applies actions that were undone, provided new actions have not been taken since the undo.

Platform considerations: CmdZ is tied to the macOS environment and Apple keyboards; Windows equivalents use Ctrl+Z. On non-Mac keyboards, users may need to map keys differently. iPadOS and other Apple platforms offer undo functionality through touch gestures (for example, shake-to-undo or trackpad gestures on iPad), and external keyboards can use the same Cmd+Z convention as macOS.

In usage, CmdZ is the most common backward-steps command for reversing recent edits, with the redo function serving as the complementary forward-step option in many, though not all, applications.