The term refers to factories that combine at least three characteristics:
Use of machinery employment of labour, and the application of regulatory measures such as the Factory Act, Disputes Act.

A small enterprise is an enterprise where the investment in equipment does not exceed Rs.10 lakhs.

On the basis of size or scale of operations, industries may be classified as:
(i) Micro Industries
(ii) Small Industries
(iii) Medium Industries and
(iv) Large Industries

Distributive service:
Transportation, warehousing, logistics, salesmanship, etc., come under this type of service.

Assembling industry which assembles different component parts to make a new product, as in the case of television, car, computer, etc.

Synthetic industry which combines various ingredients into a new product, as in the case of cement.

Analytical industry which analyses and separates different elements from the same materials, as in the case of oil refinery.

Genetic industries remain engaged in breeding plants and animals for their use in further reproduction.

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

Primary industry is concerned with production of goods with the help of nature. It is a nature-oriented industry, which requires very little human effort.

a. Agriculture
b. Farming
c. Forestry
d. Fishing
e. Horticulture

Trade is an essential part of commerce. The term 'Trade' is used to denote buying and selling.

Industry refers to economic activities, which are connected with conversion of resources into useful goods.

Commerce refers to all those activities which are necessary for bringing goods from the place of production to the place of their consumption.

Selling all the goods produced at or near the production place is not possible.Hence, goods are to be sent to different places where they are demanded. The medium which moves men and materials from one place to another place is called transport.