Use the Force
Lightsabers are the primary weapons of both Jedi and Sith, and are mostly constructed and used by those that are Force-sensitive. Lightsaber technology was developed over thousands of years. The early versions required large power sources to keep them active. Smaller power sources (crystals) were eventually discovered, making the lightsabers more efficient.
Jedi are given training lightsabers when they begin learning the ways of the Force. The lightsaber is seen as a method of measuring progress in young padawan learners. One of the finals tests of a padawan is to construct his or her own lightsaber before going through the Jedi trials. A padawan's lighsaber is usually based on the design of their master's.
The lightsaber is considered a more civilized weapon when compared to common blasters. Battles between Jedi and Sith typically are settled with a lightsaber duel, where the combatant with greater knowledge of the force is victorious. Jedi lightsabers are usually blue and green in color (although there have been other variations) while Sith lightsabers almost always have a red blade.