• Corruption in the oil industry: Tarbell's most famous work was her series of articles for McClure's Magazine, titled "The History of the Standard Oil Company." Published in 1902-1904, the series exposed the ruthless tactics used by John D. Rockefeller and Standard Oil to monopolize the oil industry. Tarbell's work helped to bring about the Sherman Antitrust Act, which broke up Standard Oil into 34 separate companies.
• Women's rights: Tarbell was also an advocate for women's rights and a member of the National American Woman Suffrage Association (NAWSA). She believed that women should have equal opportunities to men in education, employment, and political participation, and that the suffrage movement was essential to achieving these goals.
• Labor rights: Tarbell was also concerned with the plight of workers and supported the labor movement. She wrote articles about the harsh working conditions in factories and mines and advocated for laws to improve the safety and well-being of workers.
Overall, Ida Tarbell's work was instrumental in exposing corruption and unfair practices in American industry and society, and in promoting the causes of women's rights and labor rights. She was a courageous and influential figure in the Progressive Era.