What were the important Enlightment ideas which played a key role in these revolutions?
I will assume from your other questions that you are asking about the French and American Revolutions. We could say that other revolutions, such as those in Haiti and the Spanish colonies in the Americas, were also caused by some of these same Enlightenment ideas. We can identify at least three major ideas of the Enlightenment that played key roles in these revolutions.
The first of these ideas is the idea of popular sovereignty. This is the idea that governments were only legitimate if they got their powers from the consent of the people. It also holds that the people should have the ultimate power over their government. Both the French and American Revolutions were based in large part on the desire to take power away from aristocratic elites and give that power to the people.
The second idea is the idea of individual freedom. Many Enlightenment thinkers believed that people have certain rights simply by virtue of the fact that they are human. In pre-Revolutionary times, these rights were not protected from government infringement. One major goal of the revolutions was to make sure that governments would respect these rights.
The final idea is that of political and legal equality. Before the revolutions, there were clear hierarchies within society. Some people had more rights and power simply because of the status into which they were born. This is, of course, completely antithetical to the ideas of political and legal equality. One reason why people rebelled was because they wanted to be treated equally regardless of the station into which they were born.
These Enlightenment ideas helped to drive the American and French Revolutions.