Trade unions are associations of employees whose purpose is to regulate relations between workers and employers through collective bargaining. They serve protective, fraternal, political, and social functions for workers. Objectives of trade unions include wages, working conditions, discipline, employee-employer relations, and welfare. There are different types of trade unions like craft unions, industrial unions, and general unions. Problems faced by trade unions include leadership issues, multiple unions, lack of funding, and lack of interest. Measures to strengthen unions include forming a united labor front, developing internal leadership, and collecting membership fees.