Grey hat Grey hat The term "grey hat", alternatively spelled as "greyhat" or "gray hat", refers to a computer hacker or computer security expert who may sometimes violate laws or typical ethical standards, but does not have the malicious intent typical of a black hat hacker. The term began to be used in the late 1990s, derived from the concepts of "white hat" and "black hat" hackers. When a white hat hacker discovers a vulnerability, they will exploit it only with permission and not divulge its existence until it has been fixed, whereas the black hat will illegally exploit it and/or tell
Black mourning were specified in an unofficial dress code: "non-reflective black paramatta and crape for the first year of deepest mourning, followed by nine months of dullish black silk, heavily trimmed with crape, and then three months when crape was discarded. Paramatta was a fabric of combined silk and wool or cotton; crape was a harsh black silk fabric with a crimped appearance produced by heat. Widows were allowed to change into the colors of half-mourning, such as gray and lavender, black and white, for the final six months." A "black day" (or week or month) usually refers to tragic date.