Service industries

The tertiary sector or service sector is the third of the three economic sectors of the three-sector theory. The others are the secondary sector (approximately the same as manufacturing), and the primary sector (raw materials).

The service sector consists of the parts of the economy, i.e. activities where people offer their knowledge and time to improve productivity, performance, potential, and sustainability, which is termed as affective labor. The basic characteristic of this sector is the production of services instead of end products. Services (also known as "intangible goods") include attention, advice, access, experience, and discussion. The production of information has long been regarded as a service, but some economists now attribute it to a fourth sector, the quaternary sector.

The tertiary sector of industry involves the provision of services to other businesses as well as final consumers. Services may involve the transport, distribution and sale of goods from producer to a consumer, as may happen in wholesaling and retailing, or may involve the provision of a service, such as in pest control or entertainment. The goods may be transformed in the process of providing the service, as happens in the restaurant industry. However, the focus is on people interacting with people and serving the customer rather than transforming physical goods.

It is sometimes hard to define whether a given company is part of the secondary or tertiary sector. And it is not only companies that have been classified as part of that sector in some schemes; government and its services such as police or military, and non-profit organizations such as charities or research associations can also be seen as part of that sector.

...
Wikipedia