Feminism evolved in the 19th century in Western countries to advocate for women's freedom and equality. It has been divided into three waves. The first wave in the 19th-early 20th centuries focused on suffrage and property rights. The second wave in the 1960s dealt with legal and social inequalities. The third wave since the 1990s emphasizes intersectionality and diversity among women. Key feminist theories include liberal feminism seeking political/legal equality, radical feminism challenging patriarchy, and socialist feminism viewing oppression through capitalism.