Mysticism
Glossary of Kabbalah
From the Bnei Baruch World Center for Kabbalah Studies comes this glossary of kabbalistic terms in browsable form. A Hebrew-Hebrew version of the glossary is also available.
Kabbalah World Center
The Bnei Baruch Institute provides a guide to Kabbalah, along with daily lessons and a list of places where you can study.
Or HaSulam
Or HaSulam Online from the Ashlag Heritage Foundation is a comprehensive platform for searching and studying Kabbalah. It includes a glossary, a subject index of kabbalistic concepts, a complete library of the published and unpublished writings of The Ari-Rabbi Yitzchak Luria, an audio and video library related to his work and that of other commentators on the Kabbalah and a store from which you can order material.
The Kabbalah Centre
Based in Haifa, Israel, the website of this group provides information about topics in Kabbalah and learning opportunities worldwide.