Everyone's answer to this question will be different, but for me the three most influential changes to American society have been the civil rights movement, the women's rights movement, and the information revolution. These three events have created mainly positive changes for the United States and have touched every citizen.

The civil rights movement ended segregation, a custom and statute that had existed since the 1800's. The civil rights movement made it illegal to discriminate in housing and hiring practices. It also made violence against minority groups a hate crime. The civil rights movement has made the resources of the United States more open for all citizens. The nonviolent protests of the civil rights movement have served as an inspiration for other groups seeking equality. Students study the writings of Martin Luther King Jr. in order to learn about his rhetoric and protest techniques.

The women's rights movement also transformed US society. Women argued against discriminatory hiring practices, and the fight to end the gender wage gap continues today. Women successfully argued to legalize abortion in the court case Roe v. Wade. Women also argued successfully for more access to campus extracurricular sports with Title IX legislation.

The Information Revolution has also radically changed American society. Students from all over the world now have access to academic experts thanks to the internet. Millions of people can learn anything they want for free. The internet has also created many opportunities for sales and advertising that continue to drive the economy. The Internet also brings instantaneous news to anyone who is willing to look.

When one considers the question, one must consider which changes influenced the largest portion of American society. The civil rights movement, the women's rights movement, and the Information Revolution led to the greatest amount of change for the greatest amount of people in the United States.