1. Role of Pressure groups in Politics

2. According to H. Zeigler
Pressure groups are an organized aggregate which seems to influence the context of the government decisions without attempting to its members informal governmental capacities.

3. V. O. Key defined Pressure Groups as, Private associations formed to influence public policy. In short pressure groups are associations of people having common interests who try to achieve the object by influencing the government. They do not put up candidate in the elections.

4. Difference between Political parties and Pressure Groups
Political parties seek the votes to win whereas pressure do not,
Political parties are active political organizations whereas pressure groups are not;
Political parties take responsibility for all its acts whereas pressure groups never assume any responsibility.
the membership of the political parties are nation wide whereas the membership of a pressure group is limited to a particular area only.

5. Distinction between Pressure Groups and Lobbies
Pressure groups are interested in influencing the legislatureand public opinion to achieve their ends whereas lobbies are only interested in passage or defeat of a particular ill only;
Pressure groups are broader bodies than lobbies;

6. Kinds of Pressure Groups
Business groups and Multinational groups
Trade union
Agrarian organizations
Religious and Cultural organizations
Caste organizations
Tribal organizations
Student and Youth organization
Organizations representing the Gandhian heritage

7. Conclusion
Hence pressure groups although are not directly involved in the politics but they have a very significant role to play. As the pressure groups to a large extent helps in forming the public opinion.