well your right on some point. but hacking really dont go in to and like add a file that could track every motion you make and stuff.
most hackers are from companies that test a password network to see if a cracker can invade the network and screw around with stuff. therefore you would need to educate yourself.
but its not really hard to gain access to a computer, i think if you know how to program, you can do it since theres special made functions that show the ip,browers type,os,rev,color,ect that a person could use to go into another system. but should never be done.