Merits of division of labour
(i) It improves efficiency of labour when labour repeats doing the same tasks.
(ii) Facilitates the use of machinery in production? resulting in inventions.
(iii) Time and Materials are put to the best and most efficient use.
Demerits of division of labour
(i) Repetition of the same task makes labour to feel that the work is monotonous and stale. It kills the humanity in him.
(ii) Narrow specialization reduces the possibility of labour to find alternative avenues of employment. This results in increased unemployment.
(iii) Reduce the growth of handicrafts and the worker loses the satisfaction of having made a commodity in full.

There are three types of production
1. Primary production
2. Secondary Production
3. Tertiary or Service Production
1. Primary Production:
(i) Primary production is carried out by 'extractive' industries like agriculture, forestry, fishing, mining and oil extraction
(ii) These industries are engaged in such activities as extracting the gifts of nature from the earth's surface, from beneath the earth's surface and from the oceans.
2. Secondary Production:
(i) This includes production in manufacturing industry, turning out semi-finished and finished goods from raw materials and intermediate goods, conversion of flour into bread or iron ore into finished steel.
(ii) They are described as manufacturing and construction industries.
(iii) Such as the manufacture of cars, furnishing, clothing and chemicals, as also engineering and building.
3. Tertiary Production:
(i) Industries in the tertiary sector produce all those services which enable the finished goods to be put in the hands of consumers.
(ii) These services are supplied to the firms in all types of industry and directly to consumers.
(iii) cover distributive traders, banking, insurance, transport and communications. Government services, such as law, administration, education, health and defence, are also included.

(i) National Party: Indian National Congress, Bharatiya Janata Party, Communist party of India.
(ii) Regional Party: All India Anna Dravida Munnetra Kazhagam, Dravida Munnatra Kazhagam, Desiya Murpokku Dravidar Kazhagam, Pattali Makkal Katchi
(iii) Registered but unrecognized party: Labour party of India, Bhartiya Panchayat party, Indian Indira Congress.

Religion means a particular system of faith and worship, which brings human being with human society. Religion, is a symbol of group identity and a cultural rallying point.
It is classified as follows
(i) Universalizing Religions: Christianity, Islam and Buddhism.
(ii) Ethnic Religions: Judaism, Hinduism and Japanese Shintoism
(iii) Tribal or Traditional Religions: Animism, Shamanism and Shaman.

(i) Thenmning water in the river erodes the landscape, which creates a steep-sided valley like the letter 'V' known as 'V' shaped valley.
(ii) Falling of river water over a vertical step in the river bed is called waterfall. lt is formed when the soft rocks are removed by erosion. E.g. Coutrallam falls across the river Chittar in Tamil Nadu.
(iii) Plunge pool is a hollow feature at the base of a waterfall which is formed by cavitation. Alluuvial fan is a deposition of sediment occurs at which the river enters a plain or the foot-hills.
(iv) As the river enters the plain it twists and turns forming large bends known as Meanders. E.g. Meanders along the River Vellar near Sethiyathope in Cuddalore District, Tamil Nadu
(v) Due to continuous erosion and deposition along the sides of the meander, the ends of the meander loop comes closer and closer. In due course of time the meander loop cuts off from the river and forms a cutoff lake, also called an Ox-bow lake.

(i) In the form of a Volcano, where magma rises upward until it erupts on the seafloor is called a "hotspot".
(ii) Thus Volcanoes makes on Island.
(iii) Ex. Hawaii Islands,

(i) Volcanoes are also grouped according to-their periodicity of eruptions such as active, dormant and extinct.
(ii) These names refer to the state of activity rather than the types of volcanoes
(iii) Active Valcanoes that erupt frequently are called active volcanoes. Most of the active volcanoes lie in the Pacific Ring of Fire belt which lies along the Pacific coast.
(iv) Mt. Stromboli in Mediterranean Sea, St.Helens in USA, Pinatubo in Philippines.
(v) Dormant volcanoes have shown no sign of activity for many years but they may become active at any time. It is also called Sleeping Volcano
(vi) Vesuvius mountain of Italy, Mt Fujiyama in Japan, Mt. Krakatoa of Indonesia are famous examples of this types.
(vii) Extinct The top of extinct volcanic mountains have been eroded. Mt Popa of Myanmar and Mt. Kilimanjaro and Mt. Kenya of Africa are examples of extinct volcanoes.

Muhammaad-bin- Tughlug was a learned but cruel man. He was a poor decision maker. There was chaos in the social, economic and political condition of the empire because of his ambiguous decisions. The first and foremost was changing the capital from Delhi to Devagiri or Daulatabad and vice versa which led to loss of money and human lives. He also ordered the revenue to be collected in money instead of grains. This move led to bankruptcy and famine. Though he was wise and learned his hasty decisions led to his downfall.

(i) Rajendra I estabished Vedic college at Ennayiram where Vedas, grammar and Upanishad were taught.
(ii) This was later followed by his successors and two more such colleges had been founded.
(iii) The Great literary works like Periyapuranam and Kamba Ramayanam belong to this period.

(i) Metals like Gold and Silver are precious and rare elements.
(ii) They are shiny, strong and have high economic value.
(iii) If such metals are used in coins in an empire, it indicates its economic prosperity