Simple ways to free space
You can employ any of the following tips to increase the free space available on your Mac OS X startup disk without altering your hardware.
Empty the Trash
As obvious as it may sound, some folks regularly Trash files but neglect to periodically empty the Trash. In Finder, select Finder > Empty Trash or, under Mac OS X 10.3 or later, you can also select Finder > Secure Empty Trash.
Do not use the Trash as a "temporary" storage area. Only put an object in the Trash if you are sure it is no longer needed.
Archive old files
Archive — move, copy and delete, or backup and remove — files you do not use regularly to CD or another backup medium.
If you have not done so already, this is an excellent time to consider implementing a comprehensive backup and recovery solution.
Mac OS X 10.3 Panther® and later has a built-in function -- Create Archive -- for creating compressed archives of files or folders. These archives are generally far smaller than the original files they contain, provided the original is not already in a compressed format. To use this function, see the following AppleCare® Knowledge Base document corresponding to the version of Mac OS X you are using:
"Mac OS X 10.4 Help: Archiving files and folders."
"Mac OS X 10.3 Help: Archiving files and folders."
Clean up system logs and temporary files
Follow the advice in our "Running Mac OS X Maintenance Scripts" FAQ to regularly execute the Mac OS X maintenance routines that clean up System logs and temporary files created as part of the UNIX® underpinnings of Mac OS X.
Remove unused localization files
If you selected the Easy Install option when installing Mac OS X, localization files for over a dozen languages are installed. These files enable the Mac OS X interface to appear in a variety of languages. You can save roughly 200Mb of hard disk space by removing these localization files.
If you only need to run your Mac in US English, download and run Bombich Software DeLocalizer.
If you wish to retain specific localizations -- such as US English and Spanish -- download and run the freeware utility Monolingual to remove only selected localization files.
Note: Be sure to thoroughly read the instructions before using these utilities. Only use versions which are compatible with the version of Mac OS X you have installed.
Delete the Previous Systems folder from a prior Archive and Install
If you have performed an Archive and Install of Mac OS X, a Previous Systems folder was created containing your prior Mac OS X System folder. Once you are satisfied that your Mac is functioning properly after an Archive and Install, you can delete the Previous Systems folder as follows:
Mac OS X 10.3 Panther® or later:
Using your Admin account, drag the Previous Systems folder to the Trash.
Type your Admin password when requested to authenticate this operation.
Empty the Trash.
Mac OS X 10.2 Jaguar: See the AppleCare Knowledge Base document "Mac OS X 10.2: How to Delete a Previous Systems Folder."
Uninstall unused applications
If your Macintosh HD > Applications folder is cluttered with:
Applications you are no longer using.
Trial software that shipped with your Mac, but which you do not intend to use.
Then uninstall them.
Uninstall Mac OS 9
If your Mac can only boot into Mac OS X and you have no need for Classic mode, you can uninstall Mac OS 9 using the instructions in the “Uninstalling Mac OS 9” section of the “Mac OS 9” chapter of Troubleshooting Mac OS X.