Have you ever wondered why there are people who age up to 100 years old and are perfectly healthy, mobile, social and happy? and then there are those who are much younger and seem to age more quickly. Their cognitive abilities, mobility, vision, hearing and standard of living are falling rapidly. …Human development consists of changes that occur from conception until death. Although changes are most apparent during early childhood, development occurs at every stage of life, including old age. Most of what society knows about old age revolves around negative views of this age group. For example, the majority of people over 65 are senile, isolated, alone and feel unhappy most of the time (lingren). However, most of these ideas are based on myths and stigmas that have been created in an attempt to understand the aging process. Recent knowledge and research on the aging process has exploded in recent decades due to the increase in the average human lifespan. lifespan, maximum lifespan and percentage of the elderly population (Weinert). This increase in the elderly population has led to a large number of elderly people in our population. According to the U.S. Census Bureau, about 13 percent of the U.S. population, or one in eight Americans, is 65 or older. One in five Americans is expected to be 65 or older by 2035 (census). This increase and expected continued growth in the elderly population makes it important to study this developmental stage to potentially better understand the true aging process and the changes that occur. This can be beneficial for many people who have a frightening perception of aging due to myths surrounding the aging process. The aging process......middle of article......the changes that occur as we age are obvious, for example, hair loss, weight gain, wrinkles and decline of hearing and vision; however, many are more gradual and less noticeable. The best theories of aging include a biopsychosocial model, where all aspects of genetic, biological, psychological and social influences are taken into account. Although there is great variability between individual differences in performance, the changes that occur during development and aging fall into three categories: physical, cognitive, and psychosocial (cite). These changes are interconnected, so changes in one category will most likely affect other areas of a person's life. Physical changes that occur as a result of development into adulthood include changes in bodily functions, physical and motor functioning, sensory systems, and in the brain.