White hat (computer security) White hat (computer security) The term "white hat" in Internet slang refers to an ethical computer hacker, or a computer security expert, who specializes in penetration testing and in other testing methodologies that ensures the security of an organization's information systems. Ethical hacking is a term meant to imply a broader category than just penetration testing. Contrasted with black hat, a malicious hacker, the name comes from Western films, where heroic and antagonistic cowboys might traditionally wear a white and a black hat respectively. While a white hat hacker hacks under good intentions with permission, and a black hat hacker
Black and white some of the early home computers; this was to accommodate black-and-white TV sets, which would display a color signal poorly. (Typically a different shading scheme would be used for the display in the black-and-white mode.) In computing terminology, "black-and-white" is sometimes used to refer to a binary image consisting solely of pure black pixels and pure white pixels; what would normally be called a black-and-white image, that is, an image containing shades of gray, is referred to in this context as grayscale. Black and white Black-and-white (B/W or B&W) images combine black and white in a continuous spectrum, producing a