Cuisine is important for many reasons. One major reason is that it is one of the first introductions a person has to another culture. Often the first thing someone will notice about another culture is the food. This allows a person to be introduced to a culture and become more comfortable with other aspects of that culture.
Another reason that cuisine is important is the role it plays in allowing human populations to adapt to their environment. A culture, in order to thrive, must be able to develop practices with respect to food production and preparation that are most beneficial for them in their local environment.
It is in this way that local human communities will be able to get the most calories and nutrients out of their natural surroundings. Cuisines differ from region to region, because the best ways to find and prepare food differs from region to region. The type of food also differs depending on local climate and ecology.