Black Hat vs White Hat

A black-hat hacker is a hacker who "violates computer security for little reason beyond maliciousness or for personal gain.

Black-hat hackers form the stereotypical, illegal hacking groups often portrayed in popular culture, and are "the epitome of all that the public fears in a computer criminal". Black-hat hackers break into secure networks to destroy, modify, or steal data; or to make the network unusable for those who are authorized to use the network. A black hat hacker is an individual with extensive computer knowledge whose purpose is to breach or bypass internet security. Black hat hackers are also known as crackers or dark-side hackers. 

The general view is that, while hackers build things, crackers break things. They are computer security hackers that break into computers and networks or also create computer viruses. The term “black hat” comes from old westerns where the bad guys usually wore black hats and the good guys wore white ones.

The term was coined by Richard Stallman, to contrast the maliciousness of a criminal hacker versus the spirit of playfulness and exploration of hacker culture, or the ethos of the white-hat hacker who performs hackerly duties to identify places to repair. 

White hat hackers also identify security weaknesses; but, instead of performing malicious attacks and theft, they expose the security flaw in such a way as to alert the owner that there is a breach so they can fix it before a black hat hacker can take advantage of it. Though they often start out as black hat hackers, white hat hackers sometimes are paid consultants or actual employees of a company that needs its systems protected.

A white hat hacker is a computer security specialist who breaks into protected systems and networks to test and asses their security. White hat hackers use their skills to improve security by exposing vulnerabilities before malicious hackers (known as black hat hackers) can detect and exploit them. Although the methods used are similar, if not identical, to those employed by malicious hackers, white hat hackers have permission to employ them against the organization that has hired them. White-hat hackers may also work in teams called "sneakers", red teams, or tiger teams.