Mac OS X
Only full-sized Apple keyboards have a Home key. On most Mac OS X applications, the key works like the original on UNIX in the days of dumb-terminals, where Home moves to the start of a document. When the key is pressed, the window scrolls to the top, while the caret position does not change at all; that is, the home key is tied to the current window, not the text box being edited. On Apple keyboards that do not have a Home key, one can press fn+← for the Home key functionality described above. To get the same result as the Windows platform (that is, going to the beginning of the current line of text), one can press ⌘ Command+←.
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