My Bad was originally My Bag. It means my fault. Yes, it also means “I'm not into to that kind of thing.” as in “That's not my bag man.” The movie Clueless got it wrong, thrusting it into the mainstream as "My bad". The phrase "My bag" was used commonly as far back as the 1940s. My father, his family and friends all used it back then in Minnesota. We used "my bag" in Kansas in the 70's and 80's. I am 44 and my wife is
33. She claims it was never my bag but she is wrong. The origin of this phrase actually comes from the card
game "Spades". The
game consists of 2 teams of 2 and each
player has to predict how many hands he can take. After the round the
player that predicted wrong often say to his partner my bag meaning my fault or my mistake. Young
people heard their parents using "My bag" at the card table and took it to the basketball court. Spades is thought to have originated in the Midwestern United States (perhaps Cincinnati, Ohio) in the late 1930s. It was said to have been invented by college students who enjoyed both Whist and Bridge. They were looking for a fast-paced
game that was competitive and strategic. The game slowly spread to other college campuses in the mid-west. The game really took off during WWII. After the
war it spread to factory break-rooms and company office lunchrooms all across the country. Today there are clubs and tournaments and it's
popular on the
internet.