High Sierra Format is the early logical file system used for CD-ROMs in 1985 and 1986. The later ECMA-119 and ISO 9660 standards are based on revised HSF.
Overview
s were originally developed for recording musical data, but soon were used for storing additional digital data types because they were equally effective for archival mass data storage. At first, every CD-ROM maker created their own format as there were no high-level standards, only the Yellow Book CD-ROM standard for the lowest level. There was a need for a standard for organizing data on compact disks into logical units such as files. In order to develop a CD-ROM file system standard, the National Information Standards Organization set up Standards Committee SC EE in July 1985. In September/ October 1985 several companies invited experts to participate in the development of a working paper for such a standard. In November 1985, representatives of computer hardware manufacturers gathered at the High Sierra Hotel and Casino near Lake Tahoe, California. This group became known as the High Sierra Group. Present at the meeting were representatives from Apple Computer, AT&T, Digital Equipment Corporation, Hitachi, LaserData, Microware, Microsoft, 3M, Philips, Reference Technology Inc., Sony Corporation, TMS Inc., VideoTools, Xebec, and Yelick. The meeting report evolved from the Yellow Book CD-ROM standard for data CDs, which was so open ended it was leading to diversification and creation of many incompatible data storage methods. The High Sierra Group Proposal was released in May 1986. A draft version was submitted to the European Computer Manufacturers Association. With changes this led to the issue of the initial edition of the ECMA-119 standard in December 1986. The ECMA submitted their standard to the International Standards Organization for fast tracking, where it was further refined into ISO 9660. For compatibility the second edition of ECMA-119 was revised to be equivalent to ISO 9660 in December 1987. was published in 1988. ECMA-119 and ISO 9660 were needed because the HSF was geared primarily towards the needs of the US market. The international extensions are the bulk of the differences between the formats. In order not to create incompatibilities, NISO suspended further work on Z39.60, which had been adopted by NISO members on 28 May 1987. It was withdrawn before final approval, in favour of ISO 9660.