Hackers illegally break into computer systems for personal gain or damage, often to steal financial information. They have in-depth technical knowledge that allows them to create hacking tools. Crackers also illegally access computer systems, but lack the technical skills of hackers. Crackers rely more on pre-existing hacking tools and cause damage through actions like replacing websites. Both hackers and crackers commit cybercrimes, but hackers do so using their own technical abilities while crackers rely on existing tools.