Love at first sight

What is love at first sight ? Is there any such thing or it is just a romantic dream ?

Lets see what happen when we see a person . He/she may look attractive to us . Now what is the next step ?It depends on whether there is any communication between them or not.

1. In case of no communication we forget him/her . Sometimes we remember , but with time new faces replace him/her.
2. Sometimes a good conversation may happen . Both will feel attracted toward each other . Now they may spend some time with each other and share their feelings. After some time , they realize that the relation is not going smooth for one or other reason and they call it off. In such cases we generally call it crush or infatuation .
   
3. But it may happen that the person involved keep on having a good relation , with time they realize they are in love . And now comes the declaration of love .

Now if we will backtrack the third case we can proclaim such love as Love at first sight .