The boys' plane crashed on a deserted island. The boys were the only humans on this island.
Ralph became leader of the boys. He used a conch to gather the attention of the boys. His conch represented power and civilization.
The boys use Piggy's glasses to light a fire. They lit the fire so that they could be saved. The fire eventually set the whole island on fire killing one of the boys. The fire represents the boys' hope of rescue but also self destruction.
Jack and Ralph had a competition to see who should be leader. At first Ralph was leader, but Jack eventually won and took over.
Simon was killed by Jack's hunters. Piggy and Ralph were left alone because Jack took over. Jack and his hunters then went to kill Piggy and Ralph. Roger pushed a boulder onto Piggy which killed him.
Before Jakc and his hunters could kill Ralph, he was saved. Him and the rest of the boys were saved by a naval officer.