2. Cabala speaks of the Four Worlds, from the most spiritual to the most material, which correspond to the consonants of Tetragrammaton.
Yod - Olam Atziluth (World of Nobility) - Divine names
Heh - Olam ha-Briah (World of Creation) - Archangels
Vau - Olam ha-Yetzirah (World of Formation) - Angels
Heh - Olam ha-Assiah (Material World) - Heavenly Spheres
Some attempt to divide the Tree of Life into four parts that correspond to the Four Worlds (Kether, Chokmah and Binah, Chesed through Yesod, and Malkuth). Others say that a complete Tree exists in each World. These two approaches are not necessarily mutually exclusive.