rm command comes with its warnings -
which were also mentioned above, as were posted in this thread in 2003 for Mac OS X 10.2, many many OS X ago. A
space in a wrong place when using rm, and you can recover the files your typos deleted from your backup.
Al3kazandram, whether you are using a computer only for recreational use or for work purposes,
always make sure you have a system for backups. And not just one -
at least two, and which are stored in different physical locations.
What if your house and computer are destroyed in fire? Then the backup somewhere else (online or at a friend's place) helps get your files back. What if your computer is stolen? What if its hard drive is fried for whatever reason? What if a software update or an infant kills your system, or a cat pees on it?
If you don't have a backup, guess what? Your work for the semester, or the whole PhD, or the dozen manuscripts for the books you have been working for in the past twelve years or the 140000 pictures of your offspring are gone. Why would you want to risk this?
Mac OS X comes with Time Machine and an easy way to set up regular backups, so all you needed was to set it up. Or just do a manual backup of the important files every week or so, to a USB drive, external drive, some online storage solution, to a DVD, or whatever you prefer.
By not having a backup, you are vulnerable to all the threads two paragraphs above, and
anything that could destroy one file or the whole system. Your computer being stolen, fried in an oven by accident (I have seen two 17" PowerBooks destroyed in the oven after some infants had put them there), peed on by a furry or unfurry animal, falling on the ground from your back, being driven over by a car (that happens too), having some update eat all your files (AddressBook eat all your contacts and phone numbers for instance, or a software write nothing but zeros on all the files that were created by it), and the list could go on.
If there are
no backups, meanwhile, shut down that system.
The files are gone, but the physical space they were located in on that drive may store its ones and zeros for a while. If you are browsing using that computer now, shut it down, and use something else. If some file, of anything the computer does, writes over it, you are out of luck.
There are solutions that may be able to help you with extracting those files thought gone from that system. Several of them are listed in other threads in this forum; the only one of the professional hard drive data extractor services I remember by name is
www.drivesavers.com.
Just like in the real life out-of-computer situations, always be prepared, and always have backups.