The term "Digestive Biscuit" is a reference to the baking soda used in its manufacture, which was originally believed to aid in digestion and settle the stomach. Prior to the appellation of the word "Digestive," the biscuits were known as "Homewheat" biscuits.
Invented by Alexander Grant, early digestives were introduced in 1892 by the British company, McVitie's. The original name, "Homewheat," was considered to bestow an advantage on the product over those of McVitie's competitors, who were using imported wheat in their biscuits as opposed to home-grown British wheat.
It is likely that the name change was little more than a marketing ploy, and that the biscuits conferred no real benefit to digestion. Although baking soda can act as an antacid, this effect is highly unlikely to have survived the cooking process. If it could, then the soda crackers being sold in Massachusetts around the same time may have been marketed in this way. They were not.
A chocolate-covered version of the Digestive Biscuit was released in 1925. The basic recipe consists of a blend of coarse wholewheat and white flours. Typically considered a confection, they are sometimes eaten with cheese. The biscuit is popular throughout the United Kingdom, Australia and among older generations of Canadians.