What is Love?

While I was browsing the www.biblegateway.com (April 6, 2007) I saw their scripture of the day and it was 1 John 3:16...

“This is how we know what love is: Jesus Christ laid down his life for us. And we ought to lay down our lives for our brothers.”
1 John 3:16

...while I was reading this scripture I remembered the Gospel of John (John 3:16).

"For God so loved the world that he gave his one and only Son,that whoever believes in him shall not perish but have eternal life."
John 3:16

Then I tried to look for the same chapter and verse on the book of 2 and 3 John...

"Grace, mercy and peace from God the Father and from Jesus Christ, the Father's Son, will be with us in truth and love."
2 John 3:16

"It gave me great joy to have some brothers come and tell about your faithfulness to the truth and how you continue to walk in the truth."
3 John 3:16

...I was amazed on how these 4 books talks about one thing... that is how Jesus showed his Love for us and how we should follow him, for what He have done for us is true love, and that's inevitably true.