Star Wars: The History Of The Lightsaber

The Many Colors of the Lightsaber

Blue Blue lightsabers are said to represent righteousness and bravery, mostly by association with what the Jedi stand for.
This color is tipically the color of the Jedi Guardian.
Yellow Yellow lightsabers are said to reflect a Jedi who has honed on their skills and balance of combat and scholarly pursuits.
This color is tipically the color of the Jedi Sentinel.
Green Green lightsabers are associated with those who value concord, harmony, are helpful, cooperative, spiritual, and demonstrate goodwill.
This color is tipically the color of the Jedi Consular.
White The way to acquire a white kyber crystal is by obtaining a red kyber crystal. This can prove to be a challenge, mostly thanks to the ability to defeat a dark side user. After the user has obtained the crystal, they would then have to cleanse the hatred from the crystal. After doing so, the kyber crystal will then turn to a white color.
Red The red lightsaber, also known as the color of the Sith.
The way that a red kyber crystal is created is by making the crystal "bleed". Makeing a crystal bleed is by filling it will the users, hate, fear, and other negative emotions.
Purple Purple lightsabers are indicated to have a more moral ambiguity, uncertainty, and reconstruction user.
Purple is a combination of red and blue, therefore, it represents the users affinity with both the light and dark sides of the Force.