The ten sefirot, arranged as the Tree of Life, map how the unknowable Infinite (Ein Sof) becomes knowable. From above downward: Keter (Crown), Chokhmah (Wisdom), Binah (Understanding), Chesed (Lovingkindness), Gevurah (Severity), Tiferet (Beauty), Netzach (Eternity), Hod (Majesty), Yesod (Foundation), Malkhut (Kingdom).
The sefirot are not separate gods or parts of God. They are modes of the one God’s self-disclosure — how the hidden becomes manifest, how the transcendent becomes immanent. The human soul mirrors the sefirot; the practice of Kabbalah is in part the cultivation of each attribute in oneself.
The Zohar is the central text elaborating their dynamics.