I'd give this book a 4.5, but opted to give it 5 stars instead of 4.
Whether you are an Extrovert or an Introvert, You'll find that if you are an Introvert that there is nothing wrong with you its just many (mostly Extroverts?) shun or think they are 'dumb or stupid' (which is quite the contrary) when in fact Introverts are incredible people and we should learn to understand them and give them their room to explore their inner mind. For Extroverts they'll (hopefully) learn that about 1/3 of the people you know are Introverts and are not quite as out going, loud persons you think they should be. Yes Introverts can become 'quasi-Extroverted' at times, but they are still an Introvert at heart.
About a few months ago I learned that I was a Introvert, I kinda thought something was wrong about me, but reading this book and doing my own research on Introversion I found comfort in what I read online and in Quiet that Introverts are amazing people.