A political system means a network of individuals, groups and organisations whose interactions, and relationships help to determine, enforce and interpret the rules and policies governing the behaviour of the society. It includes not only the governmental institutions, such as legislature, courts, or administrative agencies but also all structures in their political aspects, as Almond says.
Every political system exists within a social system or society, of which it is, really, a subsystem along with other subsystems, such as economic, cultural or educational subsystems. The society around the political system is its environment, from which it is . separated by its boundaries.
The political system consists of the following (i) Political structures, e.g. government, political parties, pressure groups, etc., (ii) political functions or roles performed by actors or agents of the political structures, (not shown in the diagram above): (iii) patterns of interaction between actors and agents and their values and attitudes called Political culture, and Public Opinion- and (iv) the political process of inputs and outputs and feedbacks. All parts of the political system interact with each other, which constitute its political process. It consists of three parts, viz., inputs, outputs and feedbacks.
The inputs are the demands of die people which they make on the government and the supports which they provide it. Demands arise from the needs, desires and expectations of the people, expressed as their opinions or public opinion or by the political parties, interest or pressure groups and other media. The supports are the values, attitudes and beliefs of the people, which form the political culture. Outputs are the decisions (rules, laws and policies) of the government made to realise the popular demands. Feedback is that part of an output which affects the input and thereby improves the quality or causes self-correction of the decision-making process of the political system.
The political system is a goal attaining subsystem of the society. The function of a political system is to convert inputs or demands of the people into outputs or decisions of the political authorities. It is a structural functional subsystem of the society, which is its environment, from which it derives its resources in order to satisfy the demands of the people. However, the environment also includes several political and social subsystems.
The political subsystems are political parties, interest or pressure groups, etc., while the social sub-systems are die families, religious communities, cultural associations and clubs, educational institutions like schools, colleges, universities, etc., commercial, industrial and other economic organisations like the factories, farms, trade unions, corporations, etc. All these political and social sub-systems are the sources of the demands which their members, or people, make on the government and also provide supports to it