Is heredity the same thing as evolution or are they two different things?
Heredity is part of evolution.
Heredity is the process by which specific traits are passed from a generation to another. Heredity include height, eye colour, hair colour and disease resistance.
Evolution is the process by which a larger part of population (if not all) suffers a change of characteristics. Examples of modern day evolution traits are high altitude breathing, missing wisdom teeth, disease resistance and drinking milk as adults.