Social organisation

Social organisation or social institution is a group of social positions, connected by social relations, performing a social role. It can be also defined in a narrow sense as any institution in a society that works to socialize the groups or people in it. Common examples include universities, governments, families, and any people or groups that you have social interactions with. It is a major sphere of social life organized to meet some human needs.

Social organisations can take many forms, depending on a social context. For example, for family context the corresponding social organisation is of course the family. For business context - an enterprise, company, corporation, etc. For educational context - school, university, etc. For political context - government, political party, and others.

Max Weber concluded that in the history of mankind, organisations evolved towards rationalisation in form of a rational-legal organisation, like bureaucracy.

Organisation vs institution
The term institution is in sociology sometimes used interchangeably with the term organisation, as when referring to a formal organisation like a hospital or a prison. In other parts of sociology, like sociology of organisations and especially new institutionalism (also new institutional economics in economics and historical institutionalism in political science, 'organisation' and 'institution' refer to two different phenomena. Organisations are social entities that have members, resources, structures, authority, boundaries, etc. Institutions are ideas about how something should be done, look or be constituted in order to be viewed as legitimate. the issue is complicated by the fact that one may talk of institutions that govern organisations and the organisation as an institution. Following new institutionalism, one can talk of the family as an organisation, meaning an entity that is made up of members (parents, children), have resources (household possessions and incomes), authority (parents are responsible for and decide over children), etc. But one can also talk of the famliy as an institution, meaning the idea of how a social entity should be constituted to be considered a family: two (no more, no less) grown up heterosexual persons of opposite sex that live together, preferably are married, and have at least one of their biological children living at home. any social entity not consistent with the institution of the family risk losing legitimacy and be sanctioned.

There is lot of difference between social organisation and institutions and it is recommended to be aware of the differences between those terms, define them clearly and not to use them interexchangably.