Hacking can involve exploiting weaknesses in computer systems or networks for various motivations such as profit, protest, challenge, enjoyment, or to help remove those weaknesses. There are different types of hackers including white hat hackers who test security to help improve it, black hat hackers who break into systems with malicious intent, and grey hat hackers who may sometimes hack legally and sometimes illegally. Hacking involves activities like cracking security on software, phreaking telecom networks, spoofing IP addresses, denial of service attacks, and port scanning to search for vulnerabilities.