Primary activity:Primary activities are directly dependent onenvironment as these refer to utilisation ofearth’s resources such as land, water,vegetation, building materials and minerals. It,thus includes, hunting and gathering, pastoralactivities, fishing, forestry, agriculture, andmining and quarrying.People engaged in primary activities are called red-collarworkers due to the outdoor nature of their work.

Secondary activity:Secondary activities add value to naturalresources by transforming raw materials intovaluable products.Secondary activities, therefore, areconcerned withmanufacturing processing andconstruction (infrastructure) industries.People engaged in secondaryactivities are called bluecollarworkers.

Tertiary activity:Tertiary activities include both productionand exchange. The production involves the‘provision’ of services that are ‘consumed. Exchange,involves trade,transport and communication facilities that areused to overcome distance.Tertiary jobs = White collar jobs.

Quaternary activity:Quaternary activities are specialized tertiary activities in the ‘KnowledgeSector’ which demands a separate classification. There has been a very high growthin demand for and consumption of information basedservices from mutual fund managersto tax consultants, software developers andstatisticians. Personnel working in officebuildings, elementary schools and universityclassrooms, hospitals and doctors’ offices,theatres, accounting and brokerage firms allbelong to this category of services.Like some of the tertiary functions,quaternary activities can also be outsourced.They are not tied to resources, affected bythe environment, or necessarily localised bymarket.