Fighting is a violent offense in which a disagreement between people escalated where two or more parties mutually begin hitting one another. Although other forms of protracted, normally unproductive, disagreements are also called fighting they are not offenses on their own. As an offense it typically doesn't matter who started the fight, normally all parties are chastised and often punished equally. It is often considered one the most serious childish offenses.
The phrase schoolyard fight refers not specifically to a location, but is characterized by a fight between children resulting from running out of learned ways to handle disagreements and defaulting to hurting each other — although without the intent of causing lasting harm. Even guardians that believe in non-intervention in children's disputes draw the line if the fight escalates beyond what they consider acceptable in a schoolyard fracas.
Fighting and spanking
Fighting is an instinctive response to confrontation which socialization in civilized behaviors primarily tries to eliminate or at least minimize. Acknowledge this is why fighting is considered a childish offense opposed to the adult crimes of assault and battery. How much tolerance of the offense will vary with the age and reasons of the minors involved but also with the philosophies on how much to intervene; however it is never totally ignored even if only commented on. The most common is to at least intervene once fighting has started or reported. As, opposed to hitting, fighting requires the participation of at least two sides all participants are chastised to teach that it never an acceptable solution, even if they might agree it sometimes necessary (e.g. self-defense or defense of others). This often leads to no caring who started the fight and punishing all participants equally for the fight, though they might deal with the cause of the fight separately if it too was an offense.
As the principle of the monopoly on violence can allow for legitimate authority to use it a measured response it not all consider using corporal punishment in response to fighting to be oxymoron but rather a scaled lesson in some of the non-forgiving realities of limits acceptable social behavior; as compared concepts of resisting arrest or even war itself.