A volume serial number is a serial number assigned to a disk volume or tape volume. It originated in 1950s in mainframe computer operating systems. In OS/360 line it is human-configurable, has a maximum length of six characters, is in uppercase, must start with a letter, and identifies a volume to the system in unique manner. For example "SYSRES" is often used for a system residence volume.
In FAT and NTFS file systems, a volume serial number is a feature used to determine if a disk is present in a drive or not, and to detect if it was exchanged with another one. This identification system was created by Microsoft and IBM during their development of OS/2. Please note this change was made in the pre-windows era with MS-DOS in 1987.
The serial number is a 32-bit number determined by the date on the current computer at the time of a disk's formatting. Previously, the method used to discern whether a disk was swapped was identified by reading the drive's volume label (much similar in concept to OS/360). However, even at that time the volume label was not required to be unique and was optional. Therefore, many users had not given disks any meaningful name and the old method failed.
Famous quotes containing the words serial number, volume, serial and/or number:
“The serial number of a human specimen is the face, that accidental and unrepeatable combination of features. It reflects neither character nor soul, nor what we call the self. The face is only the serial number of a specimen.”
—Milan Kundera (b. 1929)
“We are too civil to books. For a few golden sentences we will turn over and actually read a volume of four or five hundred pages.”
—Ralph Waldo Emerson (1803–1882)
“And the serial continues:
Pain, expiation, delight, more pain,
A frieze that lengthens continually, in the lucky way
Friezes do, and no plot is produced,
Nothing you could hang an identifying question on.”
—John Ashbery (b. 1927)
“Can it be, that the Greek grammarians invented their dual number for the particular benefit of twins?”
—Herman Melville (1819–1891)