The hasta was a wooden pole most often made of ash and a broad headed blade tip. The hasta could be used for both throwing and cutting.
Hastati were originally Roman troops armed with the hasta.
The Lancea (lance) was a spear of greater length most often used from the second line of defense, chariot or horseback. Like the Hasta, it was made of ash and featured an iron head.
The javelin was a spear intended for throwing. Its lenght was approximately 7 feet with a blade designed to penetrate like a dart. Featured an “amentum” (leather thong) tied to the shaft just behind its center of gravity, the amentum acted as a lever to accelerate the weapon for more powerful delivery.
The Pilum was a specially designed spear for the roman soldier. It combined the javelin’s Amentum with a specially designed head and a short heavy removable handle. The Pilum’s short penetrating blade was formed in a single piece with a soft iron shaft. Once the head entered the shield of an opponent, the weight of the Pilum’s handle caused the shaft to bend, making the shield difficult to use.