Although different people might define the stages in the evolution of feminism somewhat differently, there are generally said to have been three “waves” of feminism in the United States.
The beginning of the first wave of feminism in the US is most commonly associated with the Seneca Falls Convention in 1848. During this wave of feminism, the focus was on winning women the right to vote. In the United States, this right was achieved in 1920. Therefore, this is seen as the end of the first wave of feminism.
The second wave of feminism in the US is not generally said to have started until the 1950s. This wave of feminism had two main goals. First, it sought to achieve more legal equality for women in the United States. Second, it sought to do away with what it saw as sexist attitudes. In other words, it was not aiming simply at legal equality. Instead, it also wanted to achieve social equality so that women would, for example, no longer be seen as sex objects by men.
The third wave of feminism is connected with postmodernism and with the late 20th century and the present century (though there is no official starting date for it). This wave is hard to define because it has many different strands. The basic idea of this feminism seems to be that the second wave was too focused on the concerns of a certain set of white, middle to upper class women. It focuses more on the idea that women are a diverse group and that there can be many different ideas of feminism.