Throwing away a .dmg file. Does it erase your original file?

The .dmg file is a "disk image". It's a file which acts like a mounted disk.
Typically it is used to transport files from one place to another.

Yes, they take up space.

Typically, you get the .dmg from somewhere. You copy the relevant files from the .dmg to your hard drive, and you delete the .dmg. Of course, if you delete the .dmg before copying its contents to your hard drive you will lose the contents.

Here is a decent description:

http://aroundcny.com/Technofile/texts/mac042705.html

charlie

A dmg file is a container file for installers,folders, and applications.

If you run the installer from the dmg file, usually it installs the applications in the Applications folder. If they are there, their corrosponding DMG file is possible to be deleted after their disk image icon (example of one) is dragged to the trash.

If you drag a folder or application out of the above icon into the Applications folder, you can then drag the above icon to the trash, and then drag its corrosponding dmg file to the trash.

DO NOT drag the dmg file to the trash if:

1. You double clicked the application from the inside of and simply added to Dock (the translucent bar at the bottom of the screen), and wish to save that application for further use.

2. You are not cloning your machine when backing up. You'll want to save any downloaded application installers to CD in case you need to restore your system from your backup. See my backup FAQ*:

http://www.macmaps.com/backup.html

Treat dmg files as containers of disk images.
When double clicked those image files will become:


and will only exist as such until you either drag it to the trash, or reboot your Mac. Their contents must be moved if you want future access to them after deleting the dmg file.

- * Links to my pages may give me compensation.

Message was edited by: a brody

The normal procedure is to download a .dmg, copy the application from the .dmg to the Applications folder, then dismount the .dmg (click the triangle next to it on the sidebar) and drag it to the trash. Once the application has been copied to the Applications folder, the .dmg is no longer needed.

As others have stated, the DMG's are the package that is used to deliver your download.

If you delete the DMG and need to reinstall the software later you will have to download it again.

I collect them in one folder and then burn that to a CD or a DVD and add it to my growing collect on the shelf.