The need for "rules" is one of the themes in Golding's novel, Lord of the Flies. This need for rules not only develops the plot of the novel, but it also develops the characters, and we see that very quickly in the novel.
After Piggy and Ralph find the conch, and Piggy instructs Ralph to blow it to alert any other survivors, and shortly after he does, other boys arrive, and an assembly is formed, and in that assembly Ralph establishes himself as the leader of this newly established civilization, and with that he sets the first "rule" of the island. That rule is that no one can speak at an assembly without first having the conch. Thus the conch becomes an enormous symbol in Lord of the Flies; it symbolizes order through rules.