The lightsaber is easily the most iconic weapon in all of Star Wars, and here's all you need to know about how it works. Alec Guinness' Obi-Wan Kenobi described the lightsaber as "an elegant weapon for a more civilized age" when it was introduced in the first Star Wars movie, A New Hope. It is far more than a weapon, though, as viewers discovered in the prequel trilogy. "This weapon is your life," Ewan McGregor's younger Obi-Wan insisted to his student Anakin Skywalker. While the movies and TV shows are somewhat vague on how the franchise’s most important weapon actually functions, Star Wars books and comics have fleshed out more of how the lightsaber works.
Star Wars has shown many different kinds of lightsabers since their debut in 1977. From Darth Maul’s iconic double-bladed lightsaber in Star Wars: Episode I – The Phantom Menace, to Kylo Ren’s unstable crossguard in Star Wars: The Force Awakens, lightsabers have evolved from the simple blades seen in A New Hope. The weapon now comes in all kinds of shapes, colors, and sizes, but even the most sophisticated lightsaber has the same basic elements.
How A Jedi Constructs Their Lightsaber (And Why Each Is Unique) 
Crafting a lightsaber was a special rite of passage for almost every Jedi in the Order, and it was overseen by the ancient architect droid, Huyang (voiced by David Tennant in Star Wars: The Clone Wars and Ahsoka). Aspiring Jedi traveled to the frozen planet of Ilum in the Unknown Regions, a world rich in kyber crystals. There, they found the crystal that called to them, which they would use to power their first lightsaber. Each lightsaber was made up of five simple parts: the casing, the kyber crystal, the focusing lens, a blade emitter, and a power cell. "The rest is just wiring, an on/off switch and whatever fancy extra bits people want to build in," a lightsaber expert named Dr. Cuata explained to Luke Skywalker in Star Wars #35, by Charles Soule and Madibek Musabekov.
Oftentimes, younglings had difficulty crafting their first lightsabers without going into a meditative state. In both Star Wars Legends and canon, letting the Force guide them in their crafting has always been an essential step in making a lightsaber. This act often deterred those who weren’t Force-sensitive from attempting to craft a lightsaber, because fine-tuning the weapon without the Force was perilous; a poorly-constructed lightsaber can explode. With a plethora of different casings and decorative elements to choose from, almost every lightsaber was uniquely designed to perfectly suit the wielder. Most lightsabers were made of metal alloy, but some Jedi, such as Gungi the Wookiee, used wooden hilts.
The Kyber Crystal Is The Heart Of A Lightsaber 
The most crucial part of a lightsaber (as well as the rarest and most expensive) is the kyber crystal. Kyber crystals are naturally attuned and imbued with the Force itself, making them immensely powerful objects. In other words, each kyber crystal is a small, physical manifestation of the Force. Jedi younglings didn’t simply choose any crystal they found in the Ilum caves. Instead, they often searched or endured a small trial before feeling a specific kyber crystal calling to them. The crystal would then bond with the user for life through the Force.
