Kindness is marked by charitable behavior, a mild disposition, pleasantness, tenderness, and concern for others. When you do kind deeds, you do not expect anything in return. You just want to help someone in need. Hence, it can also be said that kindness is a virtue that comes from the heart. It drives you to do good deeds for the benefit of the person being helped. It is a form of selfless love that needs no public recognition.

This was one of the main topics in the bible. In Book II of "Rhetoric", Aristotle defines kindness as "helpfulness towards someone in need, not in return for anything, nor for the advantage of the helper himself/herself, but for that of the person helped".

Nietzsche considered kindness and love to be the "most curative herbs and agents in human intercourse". Kindness is considered to be one of the Knightly Virtues. In Meher Baba's teachings, God is synonymous with kindness: "God is so kind that it is impossible to imagine his unbounded kindness!"

More Info: en.wikipedia.org