The best kind of people are the ones that come into your life, and make you see the sun where you once saw clouds. The people that believe in you so much, you start to believe in you too. The people that love you, simply for being you. The once in a lifetime kind of people.
I would also add: they might not be once in a lifetime, if you are sincere, every once and while you will get to encounter one of them, they come to you to enlighten your life when darkness started to prevail.