A man living on a desert island, producing and consuming what he needs, is making a living but he is not in business. But if he produces an extra wingo and trades with the woman on the neighboring island for a framister, then they are in business. From small beginnings, great things can happen. Trade enriches both buyer and seller, making possible increased production and trade. As production and trade increase, so does specialization, which further increases production and trade.
Specialization can take many forms.
Another form of specialization occurs within a business by employment. Typically, the employer provides capital and strategy and carries the risk for the business, while the employee provides labor and other skills. All such services produce value for trade. Advertisers and brokers bring buyers and sellers together, lawyers provide knowledge and advice, insurers provide risk reduction, speculators provide capital and liquidity, and so on. What has changed is the complexity of the human relationships involved, the scale and abstractness of the values at stake, the difficulty of evaluating the merits of competing values, and accordingly the ease with which errors about values and how to get them can be made.