Sabre Versus Sword
I recently had the opportunity to speak to a Hungarian re-enactor, Szilard Vadasz, who taught me the difference between a heavy sword vs. a sabre. Here is a summary of his thoughts:
A sabre is curved and one edged, with the exception, on occasion, of a small part near the tip. A classic sword, however, is straight and two-edged, with the exception of the broadsword.
Heavy Knight’s sword
The sabre is more suitable for use against light cavalry because the blade is used more for slicing and sticks less often in the target It is not designed, however, to thrust into one’s opponent. The broadsword was better for this and was used more often against heavily armored enemy found more often in clashes between Western cavalry.
Heavy Sabre (probably used by Vlad Dracula)
Until Western armies became exclusively composed of light cavalry, the sabre was used more often in the Eastern areas against the Muslims, where clashes frequently took place between Western-allied hussar light cavalry and Muslim light cavalry. The English recognized this principle when they used sabres in their Eastern expeditions.
Straight swords were used less often in these encounters for a number of reasons. For one, it was more difficult to hit another fast rider with a straight sword, for another, the impact of using a sword when charging on a horse makes holding the weapon unwieldy. The lance is better adapted for this.
But to get a full-view, the hussars (hungarian and slav professional light cavalry) had a thrusting weapon too.
Hegyes tőr, or Panzerstecker
From the second-half of the 16th century, when using the pistols became more commonly on the battlefield, the hussars dispensed with the lance and got a shorter weapon, a long dagger, its blade sometimes had a cubic shape. German name: panzerstecker, hungarian: hegyes tőr. They used it as second weapon against the plate-armored heavy cavalry. In encounters they chose the weapon wisely, always adapting it to the enemy.