This chapter explains the key characteristics of automobile warranty data along with certain important definitions. Section 2.1 takes a look at certain key points in the life cycle of a vehicle. Section 2.2 provides steps involved in a warranty claim process. Section 2.3 details certain striking features of the warranty data. Section 2.4 then provides the causes that lead to unclean warranty data and also defines different types of incompleteness that warranty data exhibit.