They were original in the 1984 Macintosh OS (before it had a name), and published in the first edition (1987) of the Apple Human Interface Guidelines.
Just two of the things Microsoft copied successfully. :)
Eh, they were definitely from Xerox (so it would be unclear since that both Windows and the Mac System Software derived some of their UI elements from Xerox experiments)
Eh, they were definitely from Xerox (so it would be unclear since that both Windows and the Mac System Software derived some of their UI elements from Xerox experiments)