Ring 0 is one of the privilege levels[?] in which an x86 processor can operate at any time. The others are rings 1[?], 2[?] and 3[?]. Of these most of the operating systems including Linux use only two levels, namely Ring 0 and Ring 3. Ring 0 is the highest privilege level and is the level at which the operating system kernel runs (kernel mode). Ring 3 is the lowest privilege level and is the level at which user applications are run.
... author, winner of the Nobel Prize in literature
May 11 - Salvador Dalí, artist
May 17 - Jean Gabin[?], actor (+ 1976)
May 21 - Fats Waller, pianist (+ 1943)
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