Dar is a backup and archiving utility with a particular emphasis on correctness and precision. Unlike archiving tools that only replicate file contents, Dar works to exactly recreate hardlinked files, extended attributes of various types, macOS resource forks, file sparseness, and a variety of other file attributes. Dar also takes steps to work correctly when backing up a live filesystem (one that may be modified while the backup is running). If a file is modified while being backed up, Dar can detect this and retry that file several times. If the file is being repeatedly modified such that Dar is unable to get a clean copy of the file, this file will be flagged as 'dirty' so that the user can be notified of the potential problems. Most other archiving tools make no attempt to detect or correct this situation. In addition to full backups, Dar can also produce incremental, differential, and decremental backups. Backups can be encrypted, compressed, and split into fixed-size "slices" (e.g., for burning to a set of DVDs). Under the Asking for Support section of the Dar site, users can locate both a tutorial and a mini how-to demonstrating typical Dar usage. Under the Download section, users can locate installers for Windows and macOS systems. Users of Linux and BSD systems can find Dar in their OS package manager.