Security hacker little reason beyond maliciousness or for personal gain" (Moore, 2005). The term was coined by Richard Stallman, to contrast the maliciousness of a criminal hacker versus the spirit of playfulness and exploration in hacker culture, or the ethos of the white hat hacker who performs hacking duties to identify places to repair or as a means of legitimate employment. 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". A grey hat hacker lies between a black hat and a white hat
Severin Hacker Severin Hacker Severin Hacker (born 1984) is a Swiss computer scientist who is the co-founder and CTO of Duolingo, a popular language-learning platform. Hacker was born and raised in Zug and studied at ETH Zurich. He moved to Pittsburgh to study at Carnegie Mellon University where he co-founded Duolingo with Luis von Ahn in 2009. He received his BS in Computer Science from ETH Zurich in 2006 and his PhD in Computer Science from Carnegie Mellon University in 2014. Initially, Hacker and his former graduate advisor, Luis von Ahn, wanted to develop an application that could translate internet sites, so