Soup is a food that is made by combining ingredients such as meat and vegetables in stock or hot/boiling water, until the flavor is extracted, forming a broth. thumb|250px|right|Romanian potato soup

Traditionally, soups are classified into two broad groups: clear soups and thick soups. The established French classifications of clear soups are bouillon and consommé. Thick soups are classified depending upon the type of thickening agent used: purées are vegetable soups thickened with starch; bisques are made from puréed shellfish or vegetables thickened with cream; cream soups may be thickened with béchamel sauce; and veloutés are thickened with eggs, butter and cream. Other ingredients commonly used to thicken soups and broths include rice, flour, and grain.

History

left|thumb|William-Adolphe Bouguereau Soup (1865)

One of the first types of soups can be dated to about 6000 BC. Boiling was not a common cooking technique until the invention of waterproof containers (which probably came in the form of pouches made of clay or animal skin) about 9,000 years ago.

The word soup originates from "sop", a dish originally consisting of a soup or thick stew which was soaked up with pieces of bread. The modern meaning of sop has been limited to just the bread intended to be dipped.

The word restaurant was first used in France in the 16th century, to describe a highly concentrated, inexpensive soup, sold by street vendors called restaurer, that was advertised as an antidote to physical exhaustion. In 1765, a Parisian entrepreneur opened a shop specializing in restaurers. This prompted the use of the modern word restaurant to describe the shops.

In America, the first colonial cookbook was published by William Parks in Williamsburg, Virginia, in 1742, based on Eliza Smith's The Compleat Housewife; or Accomplished Gentlewoman's Companion and it included several recipes for soups and bisques. A 1772 cookbook, The Frugal Housewife, contained an entire chapter on the topic. English cooking dominated early colonial cooking; but as new immigrants arrived from other countries, other national soups gained popularity. In particular, German immigrants living in Pennsylvania were famous for their potato soups. In 1794, Jean Baptiste Gilbert Payplat dis Julien, a refugee from the French Revolution, opened an eating establishment in Boston called Restorator, and became known as "The Prince of Soups." The first American cooking pamphlet dedicated to soup recipes was written in 1882 by Emma Ewing: Soups and Soup Making.

Portable soup was devised in the 18th century by boiling seasoned meat until a thick, resinous syrup was left that could be dried and stored for months at a time. The Japanese miso is an example of a concentrated soup paste.