File systems have been developed by companies to meet their specific needs, by hobbyists, or adapted from Unix, Microsoft Windows, and other operating systems. Linux has full support for XFS and JFS, FAT (the DOS file system), and HFS, the main file system for the Macintosh. Support for Microsoft Windows NT's NTFS file system has been developed and is now comparable with other native Unix file systems. CDs, DVDs, and Blu-ray discs' ISO 9660 and Universal Disk Format (UDF) are supported.