Hackers are people that feel the need to invade other people's personal space. There are different hackers: good ones that find new ways to make Computers safer, ones that tweak computers to do stuff that they shouldnt be doing, but they arent doing any harm or anything illegal, and the ones that try to steal information via virus, remote attack, etc. Hackers use different methods of hacking. There are hundreds of them. The most popular is the Denial of Service (DoS) and remote assistance. Dos is when the hacker tries to temporarily overload your computer, so they can bypass security. Remote assistance is where the Windows OS allows other computers to take control of other computers. this can be useful for a company network, or somebody helping with a problem, but is huge vulnerability. Hope this helps.