What Unconditional Love Is

What do we exactly mean when we say unconditional love? In my own understanding, unconditional love is like the love of God towards mankind, God gives love without anything He wants to receive. He provides sunlight, air, rain, trees etc for us to take care of what He has given. Unconditional love has a purpose, and it's a blessing. 

Romantically if you love someone but he or she doesn't reciprocate your love but you expect that person to reciprocate your feelings, that is not unconditional love, because you may have the demands towards that person to love you. Whatever your motives is, so that it will fill the space in your heart, it is not unconditional love. I believe that unconditional love has it's own way to developing it, sometimes we don't really know it is happening.

If you love someone, you wouldn't expect someone to love you inasmuch as you love that person..that is my honest understanding about unconditional love..no feelings of bitterness, frustration or anger because that person doesn't reciprocate your feelings.