NTBACKUP is a built-in backup application introduced in Windows NT and included with Windows 2000, Windows XP Pro, Windows 8, as well as Windows Server versions 2003, 2008, and 2012. NTBACKUP is not installed by default in XP Home Edition.
How To Use The Backup Utility In Windows XP
How to install NTBACKUP on Windows XP Home
Manually Edit Ntbackup.exe Selection Script Files
The ntbackup command is not available in Windows Vista or Windows Server 2008. Instead, you should use the wbadmin command and subcommands to back up and restore your computer and files from a command prompt.
You cannot recover backups that you created with ntbackup by using wbadmin. However, a version of ntbackup is available as a download for Windows Server 2008 and Windows Vista users who want to recover backups that they created using ntbackup. This downloadable version of ntbackup enables you to perform recoveries only of legacy backups, and it cannot be used on computers running Windows Server 2008 or Windows Vista to create new backups. To download this version of ntbackup, see Windows NT Backup - Restore Utility.
New data and files are generally written to the first available space on a disk drive. Over time, files are changed, re-wriiten, or deleted, and open up new areas of available disk space. This open space may in turn be used by another application or file for storage creating a scattered, or fragmented structure to related data. This creates a situation where the disk heads are required to increase travel for reading and writing data and efficiency suffers.
The DEFRAG utility is used to analyze the fragmentation of files and folders on local drives and reconstruct the data into contiguous order.
More on DEFRAG