PowerBook G3 Series computers use a new, improved file format called Mac OS Extended format (sometimes called HFS Plus). Mac OS Extended format has two benefits: it increases the number of files you can store on your hard disk, and it lets your computer work with data more efficiently than previous formats.

Note : Macintosh PowerBook G3 Series computers should not be confused with Macintosh PowerBook G3 computers. Though the names are similar, there are significant differences. To visually identify which type of computer you have, close the display and inspect the display case. A Macintosh PowerBook G3 has a small, six-color Apple logo on the display case. A Macintosh PowerBook G3 Series computer has a large Apple logo on the display case that is not six-colored.