What does it mean to be a citizen of the world?

To me a citizen of the world is someone that believes in themselves and helps others. To believe in yourself you need to set goals and follow your dreams. Citizens need to try their hardest and never quit. Also citizens of the world should help people. There are many different ways to help people. Some ways is to just hold the door open, tutor someone, clean the environment, etc. People need to care for others. This is what it means to be a citizen to me.