Visual mnemonics are a type of mnemonic that work by associating an image with characters or objects whose name sounds like the item that has to be memorized. Examples Digits Digits can be memorized by their shapes, so that: 0 -looks like an egg, or a ball; 1 -a pencil, or a candle; 2 -a duck, or a swan; 3 -an ear; a pair of pouted lips. 4 -a sail, a yacht; 5 -a key; 6 -a comet; 7 -a knee; 8 -a snowman, or a pair of glasses; 9 -an apostrophe, or comma. Biochemistry Biochemical cycles (i.e., the urea cycle or the citric acid cycle) and their metabolites can be represented by means of hands and fingers (visual imagery mnemonics) which are associated to tales (narrative mnemonics). A hand, depending on its characteristics (e.g. having or not having a fingernail or a nail lunula), represents a biochemical structure and its associated chemical term. A visual mnemonic for the drug hydralazine could be represented as "lazy hydra" that is lying on a beach holding a sign "NO more work". "NO" in the above case symbolizes Nitric oxide, which is related to the drug's mechanism of action. The symbols for the thirteen macronutrient elements in biology spell CHOPKINS CaFe Mg NaCl, or C. Hopkins Cafe [food tastes] m[ighty] g[ood] with salt (NaCl). Note however, that this popular and useful mnemonic is typical in that it is neither comprehensive nor context-free. Classification of some elements, such as Na, Cl and Fe, as macro- or micronutrients is arbitrary; it depends on the organisms in question, and there are several biologically important micronutrients not mentioned. Zoology An African elephant's ears are large and shaped like Africa, while an Asian elephant's ears are small and shaped like India. A Bactrian Camel's back is shaped like the letter B. A Dromedary's back is shaped like the letter D. The species of salmon can be remembered through the fingers on the hand: chum is the thumb, sockeye is your index finger (like poking someone in the eye), king is your middle finger (the largest of the fingers), silver is your ring finger, pink is the pinky finger. Calendar A mnemonic for the number of days in each month uses the knuckles (and the dips between them) of two fists, held together, moving right from the left pinky knuckle. The raised knuckles can be seen as the 31-day