What are two major methods of dating artifacts or fossils?

Two major dating methods applied to artifacts and fossils are stratagraphic dating (based upon the particular layer of rock of sediment in which the object is found) or radiometric dating (which is based on the decay rates of certain radioactive isotopes). The type of radiometric dating used depends greatly on the approximate time period you are studying and so varies depending on if the material you are studying is an artifact or a fossil. The method most commonly used in Archaeology is carbon dating.