DOS 4

DOS 4 refers to several different versions of the Disk Operating System (DOS) that were released by various companies. These versions include MS-DOS 4.0, PC DOS 4.0, and DR DOS 4.0. Each of these versions introduced new features and improvements over their predecessors.

MS-DOS 4.0

MS-DOS 4.0 was released by Microsoft in July 1988. It was a significant update from MS-DOS 3.3 and included several new features:

• Support for hard disk partitions larger than 32 MB.
• Introduction of the DOS Shell, a graphical file management tool.
• Enhanced memory management capabilities.
• Improved support for internationalization and localization.

Features

• DOS Shell: A graphical interface for managing files and directories.
• Large Disk Support: Ability to handle partitions larger than 32 MB.
• Memory Management: Enhanced support for EMS and XMS.

PC DOS 4.0

PC DOS 4.0 was released by IBM in 1988, around the same time as MS-DOS 4.0. It shared many of the same features as MS-DOS 4.0 but was tailored specifically for IBM's line of personal computers.

Features

• DOS Shell: Similar to the one in MS-DOS 4.0.
• Large Disk Support: Support for larger hard disk partitions.
• Improved Memory Management: Enhanced support for EMS and XMS.

DR DOS 4.0

DR DOS 4.0 was released by Digital Research in 1989. It was designed to be compatible with MS-DOS and PC DOS but included several unique features:

• TaskMAX: A task-switching utility that allowed users to switch between multiple applications.
• ViewMAX: A graphical file manager similar to the DOS Shell.
• Improved Memory Management: Better utilization of available memory compared to MS-DOS and PC DOS.

Features

• TaskMAX: Task-switching utility.
• ViewMAX: Graphical file manager.
• Memory Management: Enhanced memory management capabilities.

Related Pages

• MS-DOS
• PC DOS
• DR DOS
• DOS Shell
• Expanded Memory Specification
• Extended Memory Specification

See Also

• List of DOS commands
• Comparison of DOS operating systems
• History of Microsoft Windows