Tradition holds that terma may be a physical object such as a text or ritual implement that is buried in the ground (or earth), hidden in a rock or crystal, secreted in a herb, or a tree, hidden in a lake (or water), or hidden in the sky (space). Though a literal understanding of terma is "hidden treasure", and sometimes refers to objects that are hidden away, the teachings associated should be understood as being 'concealed within the mind of the guru', that is, the true place of concealment is in the tertön's nature or essence of mind. If the concealed or encoded teaching or object is a text, it is often written in dakini script, a non-human type of code or writing that only a tertön can decipher.
Fremantle (2001: p. 19) states:
...termas are not always made public right away. The conditions may not be right; people may not yet be ready for them; and further instructions may need to be revealed to clarify their meaning. Often, the tertön himself has to practice them for many years.
In this way, one may see the tradition of terma and terton as analogous to that of inspiration and providing a legitimate cultural forum to ensure continuation of tantric tradition, and ensuring Tibetan Buddhism's and Bön's continued relevancy in an evolving world.
The terma tradition is particularly prevalent in, and significant to, the Nyingma lineage. Two of the most famous tertön in the 20th century, Jigdral Yeshe Dorje (2nd Dudjom Rinpoche) and Dilgo Khyentse, were Nyingmapa. Tertön are also prevalent in Bön traditions and a few tertön have been Kagyupa.