"White musk" is the spice's nickname, while "musk" is its scientific name. The aroma, color, and texture of this spice may vary depending on its source and treatment, and therefore different musk varieties are sometimes distinguished based on these characteristics. For example, it is common to refer to lighter colored and softer textured ones as white musk, while darker colored and harder textured ones are called red or blood musk.
Overall, white musk and musk are two names for the same substance, and they both originate from the same animal, the musk deer.