Key Points

Manufacturing is the production of goods in large quantities after processing raw materials into more valuable products. It falls under the secondary sector of the economy.

The manufacturing sector is considered the backbone of economic development. It helps modernize agriculture, creates jobs, reduces poverty, and earns foreign exchange through exports.

Agriculture and industry are not exclusive of each other and move hand in hand. Industries depend on agriculture for raw materials and sell products like fertilizers and irrigation pumps to farmers.

Industries are classified as agro-based (cotton, sugar) using agricultural raw materials, or mineral-based (iron and steel, cement) using minerals and metals.

Basic or key industries, like iron and steel, supply their products as raw materials to other industries. Consumer industries, like sugar and paper, produce goods for direct use by consumers.

Industries are classified as public sector (government owned), private sector (individually owned), joint sector (public-private partnership), or cooperative sector (owned by producers or workers).

The first successful textile mill was established in Mumbai in 1854. The industry is concentrated in Maharashtra and Gujarat due to availability of raw cotton, transport, and a moist climate.

India is the largest producer of raw jute. Most mills are located in West Bengal along the Hugli river due to proximity to jute areas, water transport, and cheap labour.

The raw material, sugarcane, is bulky and its sucrose content reduces during transport. The industry is shifting to southern and western states where cane has higher sucrose content and a longer crushing season.

This is a basic and heavy industry, as its raw materials and finished goods are heavy. It requires iron ore, coking coal, and limestone in an approximate ratio of $4:2:1$.

Aluminium smelting is the second most important metallurgical industry. Its location is determined by a regular supply of electricity and an assured source of its raw material, bauxite.

Bengaluru has emerged as the electronic capital of India. This industry has a major impact on employment generation and its growth is key to the success of IT in India.

Industries are responsible for four types of pollution that cause environmental degradation: air, water, land, and noise pollution.

Air pollution is caused by undesirable gases like sulphur dioxide ($\text{SO}_2$) and carbon monoxide ($\text{CO}$). Water pollution is caused by organic and inorganic industrial wastes discharged into water bodies.

Industrial pollution of fresh water can be reduced by reusing and recycling water, and by treating hot water and effluents in three stages: primary, secondary, and tertiary.

Air pollution can be reduced by fitting smoke stacks with filters and using cleaner fuels like oil or gas. Noise pollution can be controlled by using silencers and noise-absorbing materials.