A munafiq is a hypocrite. One who does something to show-off. Perhaps for monetary gains or simply to have the people's adulation. The hypocrisy comes to light when such a person is spotted doing something that contradicts his/her positive public image.
A hypocrite could also be someone who supports a cause or appears to uphold certain beliefs and then commits actions that fly against those beliefs.
Basically a hypocrite is one who has two faces that contradict each other. Key word being "contradict."
Interestingly enough, hypocrisy is a part of human nature. We're all hypocrites because we all have the tendency to forget and make mistakes. A parent might lecture their child to always be honest and then the child might soon catch the parent lying as well. As human beings we also criticize others for faults that we also possess to a certain degree. We might criticize someone for not wearing hijab but then we ourselves might not pray 5 times a day. We might criticize someone for being selfish and not realize that we ourselves might have been selfish during one point or another.
Contradictions are a part of human nature as is hypocrisy. In my opinion, some people are more hypocritical than others. And some people are more conscientious so they make a greater effort to practice what they preach, stick to their beliefs, and stay fairly consistent with their words and actions not only in public but also in their personal lives as well.