Solomon Asch conducted a famous conformity experiment in the 1950s. In the experiment, participants were shown card pairs with line lengths and asked to indicate which line matched on each trial. Confederates in the experiment intentionally gave incorrect answers on some trials to see if the real participants would conform. Asch found that around 75% of real participants conformed to the incorrect group answer at least once, showing the powerful influence of social pressure on conformity. Factors like group size, task difficulty, and lack of group unanimity can impact the level of conformity observed. The experiment demonstrated that people often change their own beliefs or behaviors to fit in with the group.