Some people believe that the number of spots determines the age of the ladybug, but in actuality, the number of spots has nothing to do with the age of the ladybug -- they don't gain or lose spots as they get older. The number of spots, in addition to the color and pattern of markings, will help you identify the type of ladybug it is.
Ladybugs are friendly predatory insects in the garden. The scientific name for an insect that feeds on other animals is a zoophagous insect. Ladybugs basically eat other insects, their eggs and their larvae. Ladybugs will hunt for aphids, mealybugs, whiteflies, spider mites, and scale insects.