Subjects and objects in economics
The subjects (actors) in economic study are households, business companies, the government (the state), and foreign countries. Households offer their "factors of production" to companies. This includes work, land, capital (machines, buildings) and information. They get income which they use to buy or 'consume' goods.
Business companies produce and sell goods and services and buy factors of production from households and from other companies.
The state or public sector includes institutions and organisations. The state takes some of the earnings from the business companies and households, and uses it to pay for "public goods" like streets or education, to be available for everyone. The last subject is foreign countries. This includes all households, business companies and state institutions, which are not based in one's own country. They demand and supply goods from abroad.
The objects (things acted upon) in economic study are consumer goods, capital goods, and factors of production. Consumer goods are classified as "usage goods" (for example, gasoline or toilet paper), as "purpose goods" (for example, a house or bicycle), and as "services" (for example, the work of a doctor or cleaning lady). Capital goods are goods which are necessary for producing other goods. Examples of these are buildings, equipment, and machines. Factors of production are work, ground, capital, information, and environment.