It is important also to say that these you practise of system invasion can damage its computer therefore when if this invading a system if cannot count on the action of antivirus, firewall here or any program of security of computers beyond having that to only count on an interface CLR pondendo to cause serious damages its computer therefore sends regards that if also looks for to learn techniques of maintenance of computers for eventual damages. Also the user can use these knowledge technician of invasion of systems to be developing mechanisms of blockade of invasions of computer virus as trojans among others computer virus creating manually barriers against virus of computadores.e also being able to correct antivirus imperfections using these manual knowledge technician. You can yourself also be learned these conheciemntos technician using the Linux even so this way you are complicated therefore you will have that to have a vast knowledge of Language C for among others requisite projects GNU. He understands yourself as interface CLR interfaces similars to the MS-DOS that is that they have manual commands and that they do not use mouse as right arm in interface CLR do not only exist no type of grafismo a black screen indicating the unit of its HD and in the case of the Linux the answers of the commands are in English and the commands are total different of the MS-DOS. Good this an article where we look for to also place a general aspect of the activity of Hacker and Cracker and we search to leave here some tips and concepts for that to desire to venture itself in this activity.