Final answer:
The main difference between a baby and a teenager is their stage of development, with babies in the infancy stage and teenagers in the adolescence stage. Babies grow rapidly, learn new words, develop motor skills, and explore the environment. Teenagers go through significant changes as they transition into adulthood.
Step-by-step explanation:
The main difference between an adorable little baby and a teenager is their stage of development. A baby is in the infancy stage, while a teenager is in the adolescence stage. During infancy, a child is growing rapidly, learning new words, developing motor skills, and exploring the environment. In contrast, during adolescence, a teenager goes through significant physical, cognitive, behavioral, and social changes as they transition into adulthood.