What age are babies considered toddlers?

Michelle, I believe that the child-development folks consider a child to be a toddler between the ages of 12 and 36 months. I know that the term "toddler" refers to "toddling" or learning to walk. Toddlerhood is considered the second stage of human development, after infancy and before childhood.

however, when my toddler turned 2, my e-newsletter about child development changed from "Your Toddler at 'X' months old" to "Your Preschooler at 'x' months old" I never knew the delineations, either.