In Star Wars, the lightsaber, the preferred weapon of the Sith and the Jedi, holds enormous value to its owner. Every lightsaber has kyber crystals, which could consist of simple crystals, gemstones, rocks, or other items that serve as the lightsaber's energy source. These kyber crystals resonate, producing the recognizable and electrifying "whoosh" sound everyone is familiar with and loves to create a strong, effective blade. The Jedi or Sith Lord had to infuse the crystal with the Force before putting it inside the lightsaber. The Force-user had to spend days in meditation on the crystal in order to do this.
Update August 23, 2023: This article has been updated with more information about lightsabers following the premiere episodes of Ahsoka.
The colorful lightsaber blades are a well-known fact. A Jedi's chosen class was denoted by the crystals on their lightsaber during the days of the Old Republic. Later, when most Jedi utilized blue or green crystals from Ilum caverns because of personal preference, the usage of crystals from other source worlds became less common, and this difference was abandoned. Here's what we know about each and every lightsaber color within the Star Wars universe.
Blue Lightsabers
Throughout all three Star Wars trilogies, strong Jedi like Anakin Skywalker and Obi-Wan Kenobi have been seen wielding blue lightsabers. According to the Star Wars Fandom Guide, they belong to the Jedi Guardians, a group of light-side fighting Jedi who are renowned for their battle prowess. A blue lightsaber is the most common color lightsaber featured in the franchise and was first introduced in Star Wars back in 1977 and is also the first lightsaber color audiences saw on screen.
Red Lightsabers
Sith and other dark-side users wield red lightsabers. Red lightsabers stem from toxic emotions that corrupt kyber crystals. The crystal that arises from this "bleeding" process has a reddish tint. Red lightsaber crystals may be cleansed with the Force to turn white, as will be mentioned further below. Red lightsabers have been featured by many of the franchise's villains, from Darth Vader to Kylo Ren. All Sith Inquisitors also wield red lightsabers.
Green Lightsabers
Jedi who have a particularly deep connection to the Force, such as Yoda, Qui-Gon Jinn, and a more experienced Luke Skywalker, have a tendency to utilize green lightsabers. They were once in use by the Jedi Consular class, who favored discussion over combat and saved their lightsabers for emergency situations. They had a strong interest in understanding the inner workings of the Force.
Green lightsabers actually have an interesting behind-the-scenes explanation. For both Star Wars and The Empire Strikes Back, blue was the lightsaber for Jedi, and red was for the Sith. This was going to be the defacto role for the entire franchise, but while filming Return of the Jedi, the filmmakers noted Luke's blue lightsaber would not show up against the blue sky of Tatooine, so the decision was made to change it to green. This set the precedent for multiple-color lightsabers.
Purple Lightsabers
Samuel L. Jackson, who plays Jedi Mace Windu in the prequel trilogy, said that he personally asked for his lightsaber to be colored purple when filming Star Wars: Episode II - Attack of the Clones on The Graham Norton Show in 2013. Evidently, he intended to locate himself quickly for the pivotal fight sequence on Geonosis in the film when viewing it later. George Lucas complied, and while the purple lightsaber was initially just for cosmetic reasons, it has now come to stand for a Jedi who employs both light and dark side skills.
Yellow Lightsabers
The Jedi Sentinel class, who stood as a middle ground between the Jedi Guardians and Jedi Consular, tended to favor the usage of yellow lightsabers. They studied the Force and had excellent fighting abilities. This was the explanation that was originally provided in Knights of the Old Republic, but it is unclear if this still remains canon.
Although Jedi Temple Guards used to wield yellow lightsabers, the most famous Jedi to wield a yellow lightsaber is Rey, as she built her own and was shown at the end of Star Wars: The Rise of Skywalker. Hopefully, audiences will get to see the lightsaber in action when Rey returns in her own film.
Orange Lightsabers
Orange lightsabers are somewhat rare in the Star Wars universe. The most predominant colors of lightsabers in a galaxy far, far away are the Sith lightsabers, which are red, and the Jedi lightsabers, which are more commonly blue and green. But, after Ahsoka debuted on Disney+, fans were reintroduced to the orange lightsaber once again. Two dark side agents in the series named Baylan Skoll and Shin Hati (Ray Stevenson, Ivanna Sakhno) are shown to have been wielding orange lightsabers. Notably, unlike other lightsabers with a white center, these sabers are fully colored, making them stand out even more.
There are certain lightsaber-wielders who have their foot in both camps of the dark and light side of the Force (remember, orange is a combination of red and yellow), and since Baylan Skoll appears to be from the original Jedi Order, he might be a different type of dark side users. He appears to use Jedi teachings, and his padawan even has an apprentice braid, but he employs a more brutal and violent approach to conflict than a Jedi. As Ahsoka continues, hopefully, more details will be provided about the orange lightsaber.
White Lightsabers
After Order 66, Ahsoka Tano gives up her blue lightsabers, which Anakin had given to her as a present, and pretends to be dead at the end of Star Wars: The Clone Wars. She then kills the Sixth Brother, a Jedi hunter known as an Inquisitor, and takes his red crystals for his lightsabers. By utilizing the Force to purify them, they finally return to their natural white hue. This explains why lightsabers have a white center and a colored outline. Since Ahsoka no longer sees herself as a Jedi and isn't a member of the dark side, her white lightsabers represent her unique place in the galaxy far far away.
Black Lightsabers
In the Star Wars franchise, there is only one black lightsaber known to exist. This special weapon, known as the Darksaber, was developed by Tarre Vizsla, the first Mandalorian to join the Jedi Order and later come to dominate his own planet of Mandalore. The Darksaber was stored at the Jedi Temple when he passed away, but eventually, his family, House Vizla, took possession of it.
Since then, the lightsaber has evolved into a significant representation of Mandalore. Similarly to the Elder Wand in Harry Potter, the only way to own the Darksaber is to defeat the owner in a fight. The Mandalorian goes a lot deeper into the story of the Darksaber and the story of Mandalore.