Finder Software 6.x
Early versions of the Finder would shut down whenever another program was launched, due to the single-tasking nature of the original Mac OS. The first official Macintosh unified System Software 5.x version came with Finder 6.0 and the new MultiFinder, which allowed cooperative multitasking. MultiFinder was activated with a "set startup" dialog box whose setting took effect with the next restart. System Software 6.0.x came with Finder 6.1.x and introduced a much-improved version of MultiFinder, among other enhancements. From System 6 forward, the Finder would always match the macro System version number, thus alleviating much of the confusion caused by often significantly different System and Finder versions.
The original Mac OS Finder featured a "universal Desktop," which showed the union of the contents of the invisible "Desktop Folder" on the root level of every mounted disk in System 7. This meant that files dragged from a disk to the Desktop did not always copy to the Mac's hard drive, and would disappear when the disk in question was later ejected.
A "Put Away" command premiered in System 6 which allowed users to drag icons from anywhere on their computer to the Desktop, use the file from the Desktop, and then scoot the file back to its original location with a single command.
Finder 6 also provided support for the industry standard 1.44MB floppy disk, almost doubling the previous 800K disk capacity. More importantly this new SuperDrive continued to provide support for the earlier single-sided MFS and 800K disks as well as supporting ProDOS and popular MS-DOS formats.
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