.sys
Encyclopedia
.sys is a filename extension
in Microsoft Windows
and DOS
-type operating system
.
Most .sys files are real-mode device driver
s. Certain files using this extension are not, however: MSDOS.SYS
and IO.SYS
are core operating system files in MS-DOS
and Windows 9x. The CONFIG.SYS
file contains various configuration options (as well as specifying what device drivers will be loaded).
.sys files can be found in the C:/Windows directory of Windows computers. It is found in the C:/Windows/winsxs subdirectory in later versions of Windows.
Filename extension
A filename extension is a suffix to the name of a computer file applied to indicate the encoding of its contents or usage....
in Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
and DOS
DOS
DOS, short for "Disk Operating System", is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 if one includes the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.Related...
-type operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
.
Most .sys files are real-mode device driver
Device driver
In computing, a device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device....
s. Certain files using this extension are not, however: MSDOS.SYS
MSDOS.SYS
MSDOS.SYS an important system file on MS-DOS and Windows 9x systems. It is run after IO.SYS. In MS-DOS, it contains the core operating system code, the kernel...
and IO.SYS
IO.SYS
IO.SYS is an essential part of MS-DOS and Windows 9x. It contains the default MS-DOS device drivers and the DOS initialization program.- Boot sequence :...
are core operating system files in MS-DOS
MS-DOS
MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...
and Windows 9x. The CONFIG.SYS
CONFIG.SYS
CONFIG.SYS is the primary configuration file for the DOS, OS/2 as well as similar operating systems. It is a special file that contains setup or configuration instructions for the computer system.- Usage :...
file contains various configuration options (as well as specifying what device drivers will be loaded).
.sys files can be found in the C:/Windows directory of Windows computers. It is found in the C:/Windows/winsxs subdirectory in later versions of Windows.