Transactions

In commerce, a transaction is a completed agreement between a buyer and a seller to exchange goods, services, or financial assets in return for money. Accordint to The Britannica Dictionary, a transaction is a business deal : an occurrence in which goods, services, or money are passed from one person, account, etc., to another.

More generally, you can call any exchange with another person a transaction. There are transactions involving money, ideas, and even e-mail.