The distribution of the population according to different types of occupation
is referred to as Occupational Structure.
Occupations are generally classified as:
(i) Primary activities: These include agriculture, animal husbandry, forestry, fishing, mining and quarrying, etc.
(ii) Secondary activities: These include the manufacturing industry, building and construction work, etc.
(iii) Tertiary activities: These include transport, communication, commerce, administration and other services.