קליפה is a general term for the reality of evil and impurity in the world. The קליפה is also called the "סטרא אחרא" (Aramaic: "the other side," i.e., not the side of holiness) or the חיצונים. It is called קליפה because evil is like the peel of a fruit — covering the fruit itself, though it is worthless waste in and of itself. Likewise, impurity and evil are noticeable in the world even though they are not the true reality, but rather a concealment of the divine and holy reality. Through breaking the קליפה, one reveals the truth and goodness within the world.[1]
More specifically, there are various types and levels of קליפות, which are generally divided into two categories: קליפת נוגה, which contains a mixture of good and evil, and the שלוש קליפות הטמאות, which contain only evil.
The other side[edit]
קליפות are referred to as “other g-ds” (Acheirim) because they receive from בחינת אחוריים. They also referred to as “Peaks of separation” (טוּרֵי דִפְרוּדָא) i.e., they are as haughty as mountain peaks and are thus separate from G-d.[2] [3]