Retailing is a vital commercial activity, providing customers with an opportunity to purchase goods and services from various types of merchants. The first retail outlets in America were trading posts and general stores. At trading posts, goods obtained from Native Americans were exchanged for items imported from Europe or manufactured in other parts of the country. As villages and towns grew, trading posts developed into general stores and began to sell food, farm necessities, and clothing. Typically run by a single person, these stores sometimes served as the post office and became the social and economic center of their communities. Since World War II, giant supermarkets, discount houses, chain stores, and shopping malls have grown in popularity. Even so, individually owned businesses thrive, often giving customers more personal and better-informed service.

Today, retail is a complex and diverse field. It involves the selling of all types of physical goods, such as automobile parts, pharmaceuticals, clothing, health care products, books, and food, as well as services, such as automobile repair or rug cleaning. There are about 4 million retail establishments in the United States. According to the National Retail Federation of the top 50 online retailers, nearly all have brick-and-mortar stores. The market research group Statista reports that total retail sales in 2019 were $5.47 trillion, with the vast majority of sales composed of in-store purchases. In 2019 e-commerce accounted for 10 percent of revenue in retail sales, compared to 7.1% in 2015. More than 29 million people in the U.S. are employed by retailers.

Since January 2020, the coronavirus pandemic has affected the retail industry in the United States as well as throughout the world. The closures of stores and businesses to protect the health of employees have caused retail employment and revenue to fluctuate. The long-term effects of the pandemic on the retail industry are yet to be dete...