Grey Hat Hacker- They are Skilled Hacker who sometimes act legally and sometime not. In simple word you may call a Grey Hat hacker as Hybrid between White Hat and Black Hat hacker
Black Hat Hacker- Also referred as Cracker. A Black Hat Hacker's intention is to break into others Network, and wish to secure his own machine. They often uses different techniques for breaking into systems which can involve advanced programming skills and social engineering.
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