15 years of FreeDOS
Originally released on the 28th of June 1994, FreeDOS is now 15 years old. FreeDOS is a free open source DOS (Disk Operating System) clone that was developed by Jim Hall, a former physics student at the University of Wisconsin-River Falls. It was originally named PD-DOS (Public Domain DOS) and began after Microsoft announced that it would be dropping DOS in its next release of Windows, Windows 95. The current release, version 1.0, was released in early September of 2006 and is licensed under version 2.0 of the GNU General Public License (GPLv2).
Even though (Free-) DOS itself was superseded by operating systems with graphical user interfaces (GUIs) in the mid-nineties, it's still a great example of an open source equivalent for a proprietary operating system. It supports the use of FAT32 partitions, long file names (via the DOSFN driver) and can handle up to four hard disks up to two terabytes in size. FreeDOS also includes a UDMA driver for faster disk access. FreeDOS has been used by various emulators and embedded systems and is often used to breathe life into old DOS games. Some hardware manufacturers, such as HP and Dell, have even decided to bundle FreeDOS with their systems as an option to Windows or Linux.