Ethical hacking involves a hacker agreeing with an organization or individual who authorizes the hacker to levy cyber attacks on a system or network to expose potential vulnerabilities. An ethical hacker is also sometimes referred to as a white hat hacker. Many depend on ethical hackers to identify weaknesses in their networks, endpoints, devices, or applications. The hacker informs their client as to when they will be attacking the system, as well as the scope of the attack. An ethical hacker operates within the confines of their agreement with their client. They cannot work to discover vulnerabilities and then demand payment to fix them. This is what gray hat hackers do. Ethical hackers are also different from black hat hackers, who hack to harm others or benefit themselves without permission.