The Option key may be labeled Alt, or Option, or both, and sometimes the symbol. The Option key is a (ALT) present on. It is located between the and 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. Commonly uses the symbol U+2325 ⌥ OPTION KEY to represent the Option key. From 1980 to 1984, on the, this key was known as the closed apple key, and had a black line drawing of a filled-in apple on it.
One of the biggest pet peeves for users who switch to Mac from Windows is the Delete key, because it feels backwards.To make matters worse, the vast majority of Mac users don't use the full-size.
(See for information about the history and the 'open apple'.) Since the 1990s, 'alt' typically appears on the key, as well, for use as an 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 systems. 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 and symbols. In this regard, it is akin to the, found on some IBM-compatible PC keyboards.
If you've long been a Windows user, then you're likely very used to the keyboard layout, and your muscle memory is incredibly strong, so that your pinky always lands perfectly on the shift key, and you don't even have to look to hit ctrl-alt-del. If you've just switched to Mac, then the layout is going to be a bit different and you'll have to retrain that muscle memory (I switch back and forth on a daily basis and now the only thing my muscles remember is how to be puny). Fear not, for the two are not so different after all, once you know the subtle differences.