(Abbreviation for Configure your System) This is one of the two special Batch files which Automatically Execute when the PC is started up - the other being AUTOEXEC.BAT . This File serves the purpose of giving you the opportunity to Configure your System to you own requirements. Commands in your CONFIG.SYS commonly set up your PC to work with other Peripherals such as a CD-ROM Drive . This file is normally located in the Root Directory . An example CONFIG.SYS is :-.