Come to think of it, what is love? How do we show it? What are the types? What are the forms?
Love is an abstract and it can also be physical. It comes in degrees. The author gathered facts, opinions, analyses, researches, quotes, passages and stories and gave an overview. It comes to show that it has forms. It is defined in a clear way. You may not realize it but you are in love. It may be based on your character. It may be because it is hard to ignore it, we are so lovable. From worship or love of God to romantic love. 
I hope that this answers your questions in the best way. 
Explore love with me.