White hat hacking

What I know about White hat hacking:
Honestly, I don't know anything about White hat hacking. I can infer that it is hacking and it has something to do with white hats.
What I wonder/questions I have about White hat hacking:
I want to know what it is..is it famous for hacking large corporation, people, etc. I also want to know a bit about what it involves (coding or something different).
Links I found most useful:
This website article "Famous White hat Hackers" from http://www.investopedia.com was useful because it gave me a feel to what White hat hacking is, and it also gave me example and I learned about famous White hat hackers(Steve Wozniak, Kevin Mitnick who started off as a black-hat hacker and was even arrested for hacking North American Air Defense Command computer.)
Another useful article I found was more about telling me what is White hat Hacking even tough there was some difficult words, it does give you a much more in depth explanation to what White hat Hacking is.
Things I learned about White hat hacking:
-Steve Wozniak from apple was a famous white hat hacker.
-White hat hackers are usually employed by organizations and companies who need network security.
-White hat hackers are "ethical hackers" meaning they don't hack to do malicious things, they even stop the black-hat hackers from entering/breaking in networks.
-Kevin Mitnick who started off as a black-hat hacker and was arrested for hacking a North American Air Defense Command computer.
-White hat hackers are often assigned to test out the strength of  companies/organization's security.
How this connects/relates to my life:
This all connects to my life because all of the programs that we use on a daily basis were tested on by a White hat Hacker.
Questions I still have:
I want to know about the process of hacking or how to do it.