• Society is formed by human interaction. Humans interact, communicate and construct social collectivities. These collectivities are referred to as social groups and exist in every society.
• We have something in common with others in the same group, we identify with the group, and the group can create a sense of belonging for us. However, the types of groups that exist may differ from society to society.
• Thus, social group refers to a collection of continuously interacting persons who share common interest, culture, values and norms within a given society.
• According to Horton and Hunt “Social groups are aggregates or categories of people who have a consciousness of membership and of interaction”.
• A group is also different from a category. If you are in the same category as a person, you may share similar characteristics—like age, height, or you both wear glasses, but you may not interact or feel the sense of belonging.

Social control, within sociology, refers to the many ways in which our behavior, thoughts, and appearance are regulated by the norms, rules, laws, and social structures of society. 

Functionalism assume that society benefits everyone whereas Conflict do not assume that society benefits everyone. Functionalism defends existing social arrangements whereas Conflict exaggerates tension and division in society.

Work:-  Work done W is defined as the dot product of force F and displacement s.
W = Fs
= Fs cos θ

Work done by the force is positive if the angle between force and displacement is acute (0°<θ<90°) as cos θ is positive. This signifies, when the force and displacement are in same direction, work done is positive. This work is said to be done upon the body.

A stateless society is a society that is not governed by a state, or, has no government.

What is the Definition of Cooperation

F.E. Merrill: "cooperation is a form of social interaction wherein two or more persons work together to gain a common end."

Fairchild: "cooperation is the process by which the indi­viduals or groups combine their effort, in a more or less organized way for the attainment of common objective."

A.W. Green^. "Cooperation is the continuous and com­mon endeavor of two or more persons to perform a task or to reach a goal that is commonly cherished,"

Types of Cooperation

There are two types of co-operation

1. Direct Cooperation

The task unable to be performed by an individual needs coop­eration of other people. Those things which are common to the peo­ple and they share in such things is called direct co-operation. It is the co-operation in which the participants have common interest. For example, playing, praying, studying and working together in a farm or road building and house building are the examples of direct so-operation. All the activities of social life in which interest of a group of people is involved falls in direct co-operation.

Examples of direct cooperation in societies

1. In rural communities the people co-operate in carrying the ill person to the doctor.
2. The people co-operate on marriage, birth, Eids and other occa­sions of celebration.
3. In urban community people of a political party co-operate with one another in general walks of social life.
4. In urban areas, the people of a religious sect co-operate with one another with special interest

2. Indirect Co-operation

People do unlike things for the achievement of similar goals. Division of labour and specialization in a complex society, create impersonality in human behaviour and the people of one category co-operate with the people of other categories. In this way, labour and the material products are exchanged to the satisfaction of mu­tual needs and this process involves co-operation among people. People belonging to various' castes and classes have to co-operate, sometimes, in face of common needs and a common situation con­fronting them.

Examples of Indirect Cooperation

1. The owners of a mill and its workers co-operate with one an­other.
2. The businessmen and the customers co-operate on the selling rates of the products.
3. The exogamous system of marriage is a marriage between two families of different castes and Biradris, This system is grow­ing popular in urban social life.     .
4. The people living in urban communities co-operate in different acts of social life even they belong to different professions, castes, classes, sects and political parties.
5. Co-operation among the people of different professions is a nice example of this type. In this way, they fulfil the needs of one another. This type of co-operation is indirect