Industries may be divided into three broad categories namely primary, secondary and tertiary.

• Primary industries: These include all those activities which are concerned with the extraction and production of natural resources and reproduction and development of living organisms, plants, etc.

• Secondary industries: These are concerned with using materials, which have already been extracted at the primary state. These industries process such materials to produce goods for final consumption or further processing by other industrial units

• Tertiary industries: These are concerned with providing support services to primary and secondary industries as well as activities relating to trade. These industries provide service facilities.