Your best protection against computer crimes is your own knowledge. Hopefully the suggestions above will prompt you into taking appropriate action and into protecting your computer with the suggested tools. In doing so, you'll not only protect yourself, you'll prevent the spread of these malicious activities and protect others at the same time. These old computers booted an MS-DOS type operating system from drivers stored onto a floppy disk, and in order to use a program, users would remove the boot floppy and then insert a new floppy that contained the program. The floppy not only stored the program (word processor, spreadsheet, etc.), it also stored the drivers that the program needed to communicate with the computer's hardware. File viruses may also be referred to as parasitic viruses, however should a virus work from both the boot-sector and from an infected program, the virus is then known as a multipartite virus. Why viruses exist remains a mystery, however we had privy access to the mind behind a virus programmer who explained his motivation behind his destructive inclinations. CleanSweep is a unique program that will specifically seek out files that are no longer associated with a program, and then ask if you want to delete them. The only time that you wouldn't want to delete an orphan file is if the file were an actual document that you created before deleting a program. If you were to say, uninstall Microsoft Word, all the documents that you created with Word would then turn into orphan files. Plain and simple, shareware is the best bet when you want to keep on top of the latest release of a particular program. Sure, computer stores do their best to keep their inventory up to date, but when you can download version 5.6042 of a shareware program as opposed to buying a commercial 3.0 version from the local computer shop, there's just no comparison. Performing all of these steps won't be easy. However you can help minimize resistance to your monitoring efforts by explaining why you're taking these precautions. Smaller children will probably enjoy the time you spend together at the computer, but older children and pre-teens may resent it. To help build a case for your concern, you might want to show your older children a few news stories that exemplify the dangers that unsupervised children are exposed to.