Option key

The Option key is a modifier key present on Apple keyboards. It is located between the Control key and Command key on a typical Mac keyboard. There are two option keys on modern Mac desktop and notebook keyboards, one on each side of the space bar.

Apple commonly uses the symbol U+2325 ⌥ option key to represent the Option key. From 1980 to 1984, on the Apple II family, this key was known as the closed apple key, and had a black line drawing of a filled-in apple on it. (See command key for information about the history and the "open apple".)

Since the 1990s, "alt" typically appears on the key, as well, for use as an Alt key with non-Mac software, such as Unix and Windows programs. However, the Option key in a Mac operating system functions differently from the Alt key under other Unix-like systems or Microsoft Windows. Most notably, it is not used to access menus or hotkeys, but is instead used as a modifier for other command codes, and also to provide easier access to various accents and symbols. In this regard, it is akin to the AltGr key, found on some IBM-compatible PC keyboards.

The use of the Option key is similar to that of the AltGr key on European keyboards of IBM-compatible PCs, in the sense that it can be used to type additional characters, symbols and diacritical marks. The options available differ depending on the keyboard input locale that the user has selected. For example, in the U.S. English keyboard input, ⌥ Option+a produces the "å" character, and ⌥ Option+4 produces the cent sign "¢".

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