The Punic Wars were a series of three wars fought between Rome and the Phoenician city of Carthage. They are known as the "Punic" Wars because Rome's name for Carthaginians was Punici (older Poenici, due to their Phoenician ancestry).
The primary purpose of the Punic Wars was Roman territorial expansion. The Romans were particularly interested in the Carthaginian ports. The First Punic War was simply a war in which the Romans wanted to conquer Sicily. The other Punic Wars were simply designed to punish the other side for taking over ________. As a result of these battles, Rome greatly improved its navy, inventing a new device called the raven that was a plank designed to serve as a bridge that dropped down onto the enemy's vessel. The wars were very costly and also resulted in many deaths on both sides.
Eventually, the war was taken to Africa, and Carthage was defeated at the Battle of Zama, its territory being reduced to the city itself in a striking loss of power.