The economic development of a country depends on the following factors:
(i) Availability of different types of resources.
(ii) Technical skills and technologies used by the People.
(iii) Sustainable use of nature.

Natural resources are drawn from nature and used without much modification like- the air we breathe, water in rivers and lakes, soil, etc. Whereas, human made resources are those which are made by people by changing the original form of the natural resources. For Example, Buildings, Machinery, Bridges, etc.

Generally, resources are classifiedinto three groups: Natural, Human-m-ade and Human resources.
(i) The resources which are obtained from nature and .used without making much change or modification are called as Natural Resources. For example, air, water, soil, etc.
(ii) When the original form of natural substances is changed to make them more useful, then they are known as Human-made Resources. For example, buildings, vehicles, roads, etc.
(iii) The people who serve us in various ways is known as Human Resource. They make the best use of nature. They change the natural resources into more useful form using their technical skills. For example, doctor, engineer, teacher, carpenter, etc.

The six basic principles of sustainable development are:
(i) To respect and care all forms of life.
(ii) To improve the quality of human life.
(iii) To conserve the earth's vitality and diversity. 
(iv) To minimise the depletion of natural resources.
(v) To change the personal attitude and malpractices towards the environment.
(vi) To encourage communities to care for their own environment.

(i) When the original form of a natural substance is changed to make it more useful, then it is known as Human-made Resource.
(ii) Many natural resources are used by human beings after making some changes in them in order to make them more useful, e.g., buildings, roads, machines, vehicles, etc.
(iii) Iron ore is a natural resource, but it was of no use till the human being learnt to extract iron from it.

The resources which are obtained from nature and used without much change or modification are called Natural Resources.
(i) On the basis of their origin, natural resources are classified as:
(a) Abiotic and
(b) Biotic Resources.
(ii) Non-living resources such as soils, rocks and minerals are known as Abiotic Resources, whereas the living objects or substances such as plants and animals are known as Biotic Resources.

Natural resources are classified into different groups on different basis.
These are:
(i) On the basis of their level of development and use:
(a) Actual Resources and
(b) Potential Resources.
(ii) On the basis of their origin :
(a) Abiotic and
(b) Biotic Resources.
(iii) On the basis of their distribution:
(a) Ubiquitous Resources and
(b) Localised Resources.
(iv) On the basis of stock:
(a) Renewable resources and
(b) Non-renewable resources.

As we live on the Earth, so it is our duty to ensure that:
(i) all uses of renewable resources are sustainable.
(ii) the diversity of life on the earth is conserved.
(iii) the damage to natural environmental system is minimised.

The four ways to save energy at home are:
(i) We should put light and fans off when not in use.
(ii) We should not waste water unnecessarily.
(iii) Food should be cooked in pressure cooker.
(iv) Save petrol by following driving rules properly.

Any substance used for production and is market-oriented has an economic value.
For example cotton is used in industries to produce textiles and other goods, so cotton has economic value. However, moral values and love for friends and family do not have economic value but have social value.

Differentiate between ubiquitous and localised resources are:

Differentiate between potential and actual resources are:

Human resources are important because nation's development is mostly dependent upon human resources which include human's skill, technology, thinking and knowledge, that leads to a nation's power. Only human skill and technology change the natural substances into a valuable resource.

The distribution of natural resources is uneven and very much rely on physical factors like terrain, climate and altitude which are different from place to place over the Earth surface.

Human-made resources are:
(i) Benches
(ii) Pen/pencil
(iii) Buildings
(iv) School bus
(v) Roads