Yes, it has happened (Mitnick). But usually it's very hard for such people to gain trust because of what they did in the past.
The minimum qualification to become a white hat hacker is becoming a Certified Ethical Hacker. This is a certified credential from the EC-Council for people who want to be ethical hackers.
Black hat
a white hat hacker is a white hat because he/she doesnt destroy/exploit systems he/she has broken into. and instead somehow notifies the admin of the cracked systems security holes and flaws. the black hat on the other hand is a hacking into systems (usually) only to destroy something or to steal information like bank information. and the grey hat is just in between them in some way maybe not always leaving a note to the admin telling about the flaws in the system or the loop hole he/she used. or maybe just peeking abit in the logs.
A Hacker is good, he hacks websites to find weaknesses-which he will report (he is a white hat hacker) and a cracker is a malicious user who wants to break into websites for personal gain or to vandalise it (black hat)
· White hat hackers use their skills for legitimate reasons, such as modifying software to make a program more efficient.
"White hat describes a hacker who identifies a security weakness in a computer system or network but, instead of taking malicious advantage of it, exposes the weakness in a way that will allow the system's owners to fix the breach before it is can be taken advantage by others (such as black hat hackers.) Methods of telling the owners about it range from a simple phone call through sending an e-mail note to a Webmaster or administrator all the way to leaving an electronic "calling card" in the system that makes it obvious that security has been breached. While white hat hacking is a hobby for some, others provide their services for a fee. Thus, a white hat hacker may work as a consultant or be a permanent employee on a company's payroll. A good many white hat hackers are former black hat hackers. The term comes from old Western movies, where hero's often wore white hats and the "bad guys" wore black hats." Answer from SearchSecurity.com
Such hackers are formally called "ethical hackers", though they are also referred to as "white hat hackers".
There are no correlation. "White hat", equivalent to "ethical hacker", are both colloquial terms for someone who is proficient in systems penetration testing, employed by a company or companies to test and audit enterprise infrastructures and provide feedback. Red Hat as a company develops RHEL (Red Hat Enterprise Linux), an enterprise-level Linux distribution.
There ARE no real divisions
It is impossible. It was out during the beta party and that was all.
black hat hacker
It would be defined as grey hat cracking. White, grey and black refer to the ethics of the person. White hat will only do something with consent. Black hat will do what they wish with a malicous purpose in mind. Grey hat does what they feel is right, and are not looking to create havoc. A person that bypasses security to access a terminal is a cracker, not to be confused with hacker.