How normal are couple fights?

Aren't fights supposed to be normal in a relationship? Many couples don't think so today... In a recent interview, actor John Abraham commented that he is happy with his current girlfriend Priya Runchal because they do not fight and only sometimes argue. Does that mean that a relationship atleast in the courtship period should not have disagreements or fights and if there are such fights in the relationship, is it headed for disaster? And apparently if you ask people around, most of the them seem to agree! Vijay Cherupally, an engineer says, "The courtship period is generally smooth sailing so I never had any fights with my girlfriend. It is only after we started living-in together that we started having arguments. So John could be true because he is still dating and getting to know her current girlfriend." Sidhhraj Chavda and his girlfriend Kinjal Shah were dating for 4 months and soon they started having fights. Every time there were fights, Siddhraj used to withdraw for days and then again come back to talk with Kinjal. According to Siddhraj, there can never be fights in a relationship. He says, "If you are fighting and constantly not being happy with each other, it only proves that this relationship cannot move further, I don't believe in the fact that fights make your relationship stronger." Agrees a senior journalist with a magazine, Diksha Pathak, "My courtship period was excellent. There is a major difference between the guy I dated and the guy who is my husband now. I believe it is only after you start living together you realise that there can be fights." Chintan Modi, a businessman says, "I think you only have one life to live! In this fast paced time, when you are meeting your girlfriend only in the weekend, and if she is cross with you for some or the other thing, I wonder how can there be happiness?" There is no limit on the number of fights that you are having, more important is how happy you are with that person. Guess the key to any good relationship is always communication, understanding and the 'effort' to work towards it rather than withdraw and being impatient with disagreements.