File System Windows Filesystems In a computer, a file system (sometimes written filesystem) is the way in which files are named and where they are placed logically for storage and retrieval. The DOS, Windows, OS/2, Macintosh, and UNIX-based operating systems all have file systems in which files are placed somewhere in a hierarchical (tree) structure. A file is placed in a directory (folder in Windows) or subdirectory at the desired place in the tree structure. File systems specify conventions for naming files. These conventions include the maximum number of characters in a name, which characters can be used, and, in some systems, how long the file name suffix can be. A file system also includes a format for specifying the path to a file through the structure of directories. Windows 2000 systems can support the following file systems: FAT, FAT32 NTFS - New Technology File System CDFS - Compact Disk File System UDF - Universal Disk Format for DVDs. EFS - Encrypting File Sys