Khdbdcm

KHDBDCM is a mnemonic for SI prefixes in order from greatest to least.: Kilo-, Hecto-, Deca-, Base Unit, Deci-, Centi-, and Milli-.

Several widely-used variations of KHDBDCM exist including:
*King Henry Died By Drinking Chocolate Milk
*King Henry's Dumb Blue Donkey Cried Moo
*Kiss Her Daily Because Divorce Costs Money
*Kiss Her Dad, But Don't Cry, Mom
*Kittens Hate Dogs Because Dogs can't meow
*Knives Having Double Blades Dice Cow MeatSome variations give the base unit as "m" for "metre"(khdmdcm) such as:

*King Henry Died, Mother Didn't Care Much