Growth refers to increases in size and weight, while development describes qualitative changes that lead to improved functioning. There are seven principles of development: continuous development from birth to death, progression from general to specific changes, sequential changes like puberty following physical maturity, unique timing of changes in each individual, interrelated social, mental, and emotional development, interaction between heredity and environment, and interaction between maturation and learning. Development involves physical, intellectual, emotional, and social growth over one's lifetime.

1. PSYCHOLOGY GROWTH & DEVELOPMENT