This document discusses the four levels of measurement: nominal, ordinal, interval, and ratio. It provides examples for each level and defines their key characteristics. Nominal level variables are categorical with no ordering. Ordinal level variables can be ranked but have no defined intervals. Interval level variables have equal intervals but no true zero point. Ratio level variables can be categorized, ordered, have equal intervals, and have a true zero point. It concludes by listing variables and asking the reader to identify which level of measurement each belongs to.