Untar can uncompress files from .7z, .tar, .tar.gz, .dmg.gz, .svgz, .gz, .tgz, .tar.z, .z, .Z, .tar.Z, .taz, .tar.bz, .tar.bz2, .tbz, .tbz2, .bz, .bz2, .rar, and .zip file formats.
List of supported files

Untar requires Mac OS 10.1 or later. Untar has been tested on systems running Mac OS 10.1 through 10.4. There is no guarantee or support for Mac OS 10.0 or any future Mac OS incarnation at this time.

Yes. As of Untar 1.3.1, it has been designed as a Universal Binary so it will run natively on Intel-based Macs, while still supporting PowerPC-based Macs running Mac OS 10.1 and later.

• Password-encrypted zip files are not supported under Untar.
• Occasionally, a process cannot be canceled once is has begun running. This case has been observed when opening .dmg.gz files.
• Making use of 7-zip (7z) archives requires Mac OS 10.3 or later.
• Mac OS 10.1 cannot uncompress a Bzipped tar archive (tbz) in a single step. Instead, Untar needs to uncompress the file in two separate steps.

To set Untar as the default application to uncompress and unarchive files, follow these directions:

1. Select a supported file (.tar, .gz, .tgz, .bz2, et cetera) in a Finder window.
2. Open the Get Info window by one of these methods:
   · Select Get Info from the File menu
   · Press the Control key and click with the mouse and select Get Info from the context-sensitive menu
   · Right-click on the file and select Get Info from the context-sensitive menu
   · Use the key combination ⌘-I
3. Open the Open With section. Change the drop down menu to Untar.
4. Click on the Change All button to set all of files of a particular type to open up using Untar.
5. Close the Get Info window.

The message "The application Help Viewer has unexpectedly quit. The system and other applications have not been affected." appeared while trying to open Untar Help. This is a problem usually found with the Mac OS 10.1 version of Help Viewer. This unfortunately has adverse side-effects where the Help Viewer will not open unless this folder is removed: ~/Library/Documentation/Help

A wrapper is a program which acts as a graphical front end to a system utility.

Archiving is the process of collecting and storing a group of files and directories into one file. The tar utility performs this action.

Compression is the act of shrinking the size of a file, which is quite useful in sending large files over the internet.

Untar is used to uncompress and unarchive files from a variety of formats.

GUI Tar is a more comprehensive tool which not only encompasses all of Untar's functionality, but also adds the ability to archive and compress files.

No. The .sit and .sitx files are proprietary formats developed by Allume Systems.

Tar is a UNIX utility which stands for Tape Archiver. Tar can either extract or combine files from/to a single .tar file. The UNIX manual (man) page for tar states:

The tar command creates, adds files to, or extracts files from an archive file in tar format. A tar archive is often stored on a magnetic tape, but can be a floppy or a regular disk file.

When a group of files are archived into a single file, they are not compressed. The gzip utility can take a file, such as somefile.tar, and compress it to make the file size smaller. Often, compressed and archived files will end with either the .tar.gz or .tgz extension, which signifies they have been archived and compressed.

Gunzip is the opposite of gzip, and it uncompresses a file, returning it to its original state.

• Tar archive: tar -xvf somefile.tar
• Gzipped tar archive: tar -xvzf somefile.tgz
• Bzipped tar archive: tar -xvjf somefile.tbz