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)
“There is a note in the front of the volume saying that no public reading ... may be given without first getting the author’s permission. It ought to be made much more difficult to do than that.”
—Robert Benchley (1889–1945)
“An autobiography is an obituary in serial form with the last instalment missing.”
—Quentin Crisp (b. 1908)
“Can a woman become a genius of the first class? Nobody can know unless women in general shall have equal opportunity with men in education, in vocational choice, and in social welcome of their best intellectual work for a number of generations.”
—Anna Garlin Spencer (1851–1931)