MultiFinder
MULTITASKING EXTENSION FOR CLASSIC MAC OS
Multifinder; Switcher (computer program); Switcher (software)
MultiFinder is an extension for the Apple Macintosh's classic Mac OS, introduced on August 11, 1987 and included with System Software 5.Macintosh: System Software Version History, Apple It adds cooperative multitasking of several applications at once – a great improvement over the previous Macintosh systems, which can only run one application at a time.