In the scientific community things must be organized so that they can be better evaluated. We do this in our everyday lives although we may not know it. We can identify a dog as a dog, but we can also differentiate the type of breed. We know dogs and cats are animals but they do not reporduce. Here is where the terms such as species, and viable offspring come into play.
Here is a breakdown of basic classification
Below is an example of how a grizzly bear is classified (source).
We do this with most things in our lives as we look for order. Such as with clothing: sweaters go with sweaters, shorts with shorts, etc. In the example above the Kingdom is Animalia (animals). The Phylum is Chordata, which means chordate, as in, it has a backbone, vertebrae. The class is Mammalia, mammals, which are characterized by mammary glands in females (milk) and hair/fur (these are the easily notible distinctions although there are others). Order Carnivora which means carnivores. Family Ursidae, which groups bears, and then the Genus and Species.
As we go down from Kingdom to Species we get more and more specific. Many of these classifications are done through evolutionary research, DNA analysis, and observations of the various stages of fetal development. In class, we will do a lab which will require us to classify our shoes. Please read over the lab and attached assignement.