ARCHIVED: In Mac OS X, how do I compress or decompress files?

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Compressed (i.e., archived or zipped) files may contain many separate files in one large archive, which often take up less space than the original files. Before you can read or run all the separate files and programs, you must use an archiving program to extract the files from the archive. Zip is a standard compression and archival format. If you're using Mac OS X, the operating system compresses and decompresses zip files for you.

Compressing a file or folder

  1. Highlight the selection to be compressed.
  2. Somewhere within the selected files, right-click, and then choose Compress. If you do not have a mouse with a right-click button, highlight the selection and hold down the Control key while clicking the trackpad.
  3. A .zip file will be created in the same directory as your selected files. Note that your original files (from which the compressed file was made) are not deleted automatically, and will remain in the directory.

    Note: You cannot name the zip file during its creation (the name given by default is, but you can rename it afterward. If you choose to create another compressed archive in the same folder without first moving or renaming the original one, there is a chance you will overwrite the original one.

Decompressing a file or folder

  1. Highlight and right-click the archive you wish to decompress.
  2. Choose Open. This will decompress the file or folder and place it in the same directory as the compressed file.

    Note: The compressed file is not deleted automatically and will remain in the directory also.

Using the Terminal

The Unix zip utilities are also available from the Terminal application. See About compressed files in Unix.

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Last modified on 2018-01-18 13:11:06.