Don't know what it is about Mac's but I just feel I have less ability to "get under the hood". Like when you look at the engine bay of a new car and it's all covered up by a plastic branded cover....
Anyhow, you need some more space on your hard drive? If you have been doing updates for a while, you can get some space back by deleting these update downloads.
(OSX 10.6)
1. Goto "Macintosh HD"
2. Select "Library"
3. Select "Updates" folder...
(OSX 10.7/8 that folder is hidden... see what I mean?)
1. In Finder, select "Go"
2. Select "Go to Folder"
3. Type in "~/Library" to temporarily access the Library directory in the Finder.
Now DELETE everything EXCEPT any ".plist" files.
That should give you back some space.... once you empty your trash of course!
Enjoy!