SmartDrive was a disk caching

Page cache

In computing, page cache, sometimes ambiguously called disk cache, is a "transparent" buffer of disk-backed pages kept in main memory by the operating system for quicker access. Page cache is typically implemented in kernels with the paging memory management, and is completely transparent to...

 program that shipped with 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...

 versions 4.01 through 6.22 and Windows 3.x

Windows 3.1x

Windows 3.1x is a series of 16-bit operating systems produced by Microsoft for use on personal computers. The series began with Windows 3.1, which was first sold during March 1992 as a successor to Windows 3.0...

. It improved disk transfer rates by storing frequently accessed data in the main memory. Early versions of SmartDrive were loaded through a 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 :...

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....

 named SMARTDRV.SYS. Later versions were loaded through an executable

Executable

In computing, an executable file causes a computer "to perform indicated tasks according to encoded instructions," as opposed to a data file that must be parsed by a program to be meaningful. These instructions are traditionally machine code instructions for a physical CPU...

 file named SMARTDRV.EXE, usually automatically at boot time by including the SMARTDRV.EXE command in AUTOEXEC.BAT

AUTOEXEC.BAT

AUTOEXEC.BAT is a system file found originally on DOS-type operating systems. It is a plain-text batch file that is located in the root directory of the boot device...

(or install=SMARTDRV.EXE into CONFIG.SYS), though it could still be loaded as a driver if double-buffering was required.

The Windows 2000

Windows 2000

Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...

 and XP

Windows XP

Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...

setup programs suggest that SmartDrive be used to decrease installation time when installing from MS-DOS.