Retail activity is the business of selling goods and services to customers. It involves the SALE of products in stores, online, or through other channels. The term 'retail activity' can be broken down into two words: SALE and SALES. SALE is a four-letter word that refers to the act of exchanging goods or services for money. SALES is a five-letter word that refers to the process of selling goods or services. Both terms are used to describe the same activity, but SALE is more commonly used to refer to the exchange of goods or services, while SALES is more commonly used to refer to the process of selling.