The DOS or Disk Operating System, is an operating system designed for computers, of the Inte family, belonging to IBM (International Business Machines), by Microsoft. This, at the beginning, was supposed to be the first popular interface available for these PCs; however, MS-DOS (Microsoft Operating Disk System), surpassed it in popularity. The interface of this system was characterized by being quite simple, acting through command lines, in text or alphanumeric symbols, that is, sending an instruction by entering a series of previously established codes. Time later, it would be replaced by the graphical interface of Windows.
In 1981, Microsoft made the purchase of QDOS (Quick and Dirty Operating System), to make a series of modifications to it, to later become MS-DOS 1.0. Over the years the system was improving, implementing the use of networks, in addition to allowing the presence of hard drives larger than 32 Gb. Towards version 6.0, other improvements were included, such as the doublespace, which allowed disk compression, achieving more storage space, the action of a basic antivirus, a defragmenter and a memory manager were included.
With the rapid advances that are being made in the matter, the system is completely relegated as an operating system in non-native mechanisms, and the different graphical interfaces that Windows designs are used, normally. Currently, it can be found as a "command prompt", a command program, which is run using cmd.exe. In non-native versions, MS-DOS is still used as the basis for executing the device interface.
