The type of supporting material that you employ in an essay is directly related to the claim that you make in your paper. Different claims and arguments require different levels of evidence and support. Moreover, the type of support they need will also vary. Some claims might need numerical support, while others might need the consensus of experts.
For example, imagine a historical essay that wants to prove that World War II was more deadly than World War I. This essay would most likely need statistical evidence that would come from public records. Compare this to an essay that argues that World War II had a deeper impact on culture and society than World War I. This essay will require different types of materials, such as essays written by other people supporting either position.
