Termas are key Tibetan Buddhist texts, many of which were hidden by Padmasambhava around the Tibetan region for future discovery at auspicious times. As such, they represent the only tradition of continuing revelation in Buddhism. The tradition is particularly prevalent in the Nyingma tradition.
Termas can be either of the "earth" or "mind". The former are physical objects -- which one can interpret as either the text themselves, or as physical symbols triggering a recollection of the text. The "mind" termas are states of mind discovered in meditative trance which connect the practitioner directly with the essential content of the text in one simultaneous experience. Once this has occurred, the tertön or discoverer of the terma then holds the whole text in his mind and is able to write it down at some future point. In this way, one can see the tradition of termas and tertöns as analogous to that of inspiration.
The most famous terma is the Tibetan Book of the Dead.
