The word "occult" is somewhat generic, in that most everything that isn't claimed by any of the major religions is considered to be occult (and many things that are). Even Kabbalah has been considered an occult study, perhaps because of its popularity among magi. Kabbalah was later adopted by the Golden Dawn and brought out into the open by Aleister Crowley and his protégé Israel Regardie. Since that time many authors have emphasized a syncretic approach by drawing parallels between different disciplines.
Direct insight into or perception of the occult does not consist of access to physically measurable facts, but is arrived at through the mind or the spirit. The term can refer to mental, psychological or spiritual training. It is important to note, however, that many occultists will also study science (perceiving science as a branch of Alchemy) to add validity to occult knowledge in a day and age where the mystical can easily be undermined as flights-of-fancy. An oft-cited means of gaining insight into the occult is the use of a focus. A focus may be a physical object, a ritualistic action (for example, meditation or chanting), or a medium in which one becomes wholly immersed; these are just a few examples of the vast and numerous avenues that can be explored.