.BCK File Extension
What is a BCK file?
A BCK file is a VMS/VAX BaCKup file created on a VMS VAX or VMS Alpha system. It contains a saveset of a file or volume of files on a VMS VAX or VMS Alpha system. BCK files are created to protect against the loss or corruption of data.
VMS was an enterprise-level server operating system developed by Digital Equipment. It came with a utility called BACKUP that was used to archive data. The BACKUP utility was used to create savesets that were stored in BCK files on a magnetic tape or disk.
NOTE: The VMS operating system (VAX-11/VMS, VAX/VMS) was replaced by OpenVMS.