A binary scale is a type of measurement that only has two possible values, such as on or off, yes or no, or true or false. There are several synonyms for binary scale, including dichotomous scale, two-point scale, and binary coding. The term dichotomous is derived from the Greek word "dichotomia," meaning "dividing in two." A two-point scale is also often used to refer to a binary scale, as it only has two distinct options. Binary coding is another term used to describe a binary scale, as it involves coding information using only two digits, usually 0 and 1. Whatever term is used, a binary scale is a simple but powerful tool for measuring and categorizing data.