Hacking vs. cracking is a useful system of classification, but the distinction is not absolute, there is a gray area between these two. Many well-respected hackers started their careers by compromising systems of other organizations, cracking copy-protection in commercial systems, or obtaining privileged information about proprietary systems (famously AT&T's telephone system), but these acts were committed mostly out of curiosity, as technical challenges, or as a protest of the perceived power imbalance that violates the spirit of hacking - rather than motivated by monetary gains or a desire to bring mayhem and destruction. Whether or not these activities are acceptable depends on someone's own personal interpretation in a case-by-case basis.