In many countries the age at which young person is considered a legal adult is typically 18, but in some other countries young person's legal adulthood only starts when he or she turns 21. What defines a legal adult is the ability to legally work, participate in contracts, vote, marry, give sexual consent, and join the military. However, I personally think that the proper age of being an adult should be 21. In this essay, I am going to explain the reasons for this stand.