The focus of this lesson is to begin to understand the process of claim testing. We use the term "claim testing" in Big History to mean the process that someone goes through when evaluating the truth of a statement that is made either in Big History or in other research that you might do. In general, when you encounter a claim, it’s important to ask why you should believe and trust in that claim. This is a core idea in Big History, and you should use claim testing on a regular basis throughout the course. We use claim testing not only to make sure that the information provided can be trusted, but it is also helpful as you take part in research, since the claims you might make should be supported by good evidence. Claim testing should be a part of regular Big History conversations, and by the end of the course, this should be a really easy process for you!