What was the significance of the battles at Lexington and Concord?

The significance of  Lexington and Concord is that fighting in these two towns outside Boston marked the beginning of the Revolutionary War. On the morning of April 19, 1775, British troops sent by General Thomas Gage clashed with Boston-area militia on the village green of Lexington. The British soldiers had been sent to arrest area revolutionary leaders and to confiscate a weapons and power cache at the town of Concord. Alerted to the movement of the British, militiamen poured out of the countryside, and, after the initial skirmish at Lexington, they provided serious opposition at Concord, just a few miles up the road. As the British withdrew back to Boston, they fought essentially a running battle with hundreds of militia who sniped at them from the woods, killing dozens of men. Once the British returned to the city, the militia surrounded it, occupying the surrounding heights. This was the beginning of the war that would lead to independence for what would become the United States of America.