A grocer is a bulk seller of food. Beginning as early as the 14th century, a grocer (or "purveyor") was a dealer in comestible dry goods such as spices, peppers, sugar, and (later) cocoa, tea and coffee. These items were bought in bulk, hence the term grocer from the French "grossier" meaning wholesaler, this term derived from Medieval Latin "grossarius"  from which we also derive the word gross (meaning a quantity of twelve dozen, or 144).
As increasing numbers of staple foodstuffs became available in cans and other less-perishable packaging, the trade expanded its province. Today, grocers deal in a wide range of staple food-stuffs including such perishables as meats, produce and dairy products. Such goods are, hence, groceries.
In the United States and United Kingdom, supermarkets and convenience stores are sometimes described as grocery businesses, or simply grocers.[note 1] The early supermarkets began as chains of grocer's shops. Clarence Saunders of Memphis, Tennessee invented the self-service grocery store with open stock in 1916, for which he received a US patent. Prior to this change in the way of doing business, the customer of a grocer would walk up to a counter or display and ask for the food items they wanted to purchase, or hand over a grocery list, as an order that the grocer or other clerks would then fill and charge the customer for.