If you're trying to hack someone's wifi, a useful bit of software you may want to try is called Wireshark. Wireshark is a wifi packet sniffer, which is an essential step in actually breaking into someone's wireless system. Of course, this is illegal, so make sure you're only doing it to test a network's security, or for your own educational purposes. Check out the video, follow the steps and see how secure network is. Hack, hack, hack!