NTLDR*(abbreviation*of*NT loader) is the*boot loader*for all releases of*Windows NT*operating system*up to and including*Windows XP*and*Windows Server 2003. NTLDR is typically run from the primary*hard disk drive, but it can also run from portable storage devices such as a*CD-ROM,*USB flash drive, or floppy disk. NTLDR can also load a non NT-based operating system given the appropriate*boot sector*in a file.NTLDR requires, at the minimum, the following two files to be on the*system volume:ntldr, the main boot loader itselfNTDETECT.COM, required for booting an NT-based OS, detects basic hardware information needed for successful bootAn additional important file is*boot.ini, which contains boot configuration (if missing, NTLDR will default to*\Windows*on the first partition of the first hard drive).NTLDR is launched by the*volume boot record*of system partition, which is typically written to the disk by the Windows*FORMAT*or*SYS*command.