Mardi Gras

Hey bloggers, is today Mardi Gras or Fat Tuesday, that New Orleans celebrate and party once a year day. I am wondering because all of the advertisements around me on this day I think says so. And there seems to be Mardi Gras parties listed everywhere in the newspapers. And what is the meaning of this day or holiday anyway. As that word Mardi Gras sounds as if it could be a latin or french word maybe. And is this day a masquerade for someone or something of some sort. Does Wikipedia, that internet bible dictionary have an entry for this word and the meaning of all things about and behind it. And this day of Mardi Gras seems to be the colors yellow, purple and green I think. And whatever this phrase may mean, have a great celebrate and party Mardi Gras day.