Business income is income that you receive when you sell products or services. For example, fees are business income to a professional person.
Rents are business income to a person in the real estate business.
Income received in the form of property or services must be included in income at its fair market value on the date received. Normally a business is conducted in the form of either a sole proprietorship, a partnership, or a corporation. A sole proprietorship is the simplest form of business organization. It has no existence apart from its owner. Business debts become personal debts of the owner.