There are a number of downloadable programs or hacking tools on the net. Programs such as Cain and Abel, John the Ripper and Free Scratch and Win are available. These programs enable people to scan and copy passwords, look up visited sites (Cookies) and deleted files and they gain access to networks and control computers by remotely giving commands to the computer.
Prevention can be done through the researching of such programs and finding counter measures, like regularly updating virus scans, virus databases and virus dictionaries. One can also get into the habit of deleting cookies or keeping away from sites that insist on saving cookies in order to visit the site. One can also make sure they keep away from sites that offer free software or games as they usually have Trojans or malware attached. Network administrators must be informed about such sites and techniques and find counter measures to prevent loss of information and privacy.
I believe that its bad to have such programs on the net as they encourage the invasion of privacy and increase criminality on youths and those that have nothing better to do with their time