Sefer Yetzirah (Hebrew, Sēpher Yəṣîrâh "Book of Formation," or "Book of Creation," ספר יצירה) is the title of the earliest extant book on Jewish esotericism, although some early commentators treated it as a treatise on mathematical and linguistic theory as opposed to Kabbalah. "Yetzirah" is more literally translated as "Formation"; the word "Briah" is used for "Creation".
Read more about Sefer Yetzirah: Origin, Manuscripts, Influence, Structure, The Phonetic System, Teachings, Creation, Theories of Contrast in Nature, Gnostic Elements, Date, Thelemic Interpretations, Suhuf Ibrahim, References To The Sefer Yetzirah