Archaeology is the science of learning about a culture by using the mom method. What is the mom method? Ask any mother and she can tell you, all she has to do is walk in her house and she knows what her kids and husband have been doing in her absence. The evidence she uses may be: the order the cars parked in the driveway, type of food preparation and location of dirty dishes, eagerness of pets to be let out or fed or watered, and the discarded clothing which she can use to track her family members through the house.
Real archaeologists have a tougher job then the average mom does in their detective work they use things that people who are no longer living have incidentally left behind, things such as cooking utensils, jewelry, human remains, tools, and even their garbage. Archaeologists delve into the lives of prehistoric people as well as modern man; a dig might be at the site of the lost city Pompeii, at Stonehenge or in Tucson, Arizona. The artifacts might be from 5000 or 150 years ago. If you are an Archaeologists you may be involved in finding a city lost for many thousands of years or in finding a graveyard misplaced for a couple of hundred years.
An artifact, no matter how old or unique, is of no use to an archeologists unless it is known where and under what circumstances it was found. In order for the archaeologist to make accurate deductions he needs to know where an object was located so the site is mapped in a grid pattern and before anything can be removed its gird position must be recorded, including the layer in which it was found. Also important will be its position in relationship to other artifacts found at the dig. The depth at which something is found along with knowledge of the topography of the region will give some idea of the age of an artifact but scientists also use the rate of radioactive decay of various elements and knowledge of the earth's changing magnetic field to help determine age.
Once the artifacts have been gathered, and it's a painstaking task, then they are evaluated and the past is recreated one little piece at a time by the forming of a hypothesis and the testing and discarding of these theories until one if found that offers the best explanation for the artifacts. There you have it : Archeology, the ultimate in cold case detective work!