Tanhà is craving. It is the chief root of suffering, and of the ever continuing cycle of rebirths. First, craving is of three kinds:
1 Kàma-tanhà – craving for sense-objects,
2 Bhava-tanhà – craving for rupa- and arupa-jhànas and rupa- and arupa-existences,
3 Vibhava-tanhà – craving for non-existence.
Corresponding to the six sense-objects, there are six kinds of craving:
1 rupa-tanhà – craving for visible objects,
2 sadda-tanhà – craving for sounds,
3 gandha-tanhà – craving for odours,
4 rasa-tanhà – craving for tastes,
5 photthabba-tanhà – craving for bodily impressions.
6 dhamma-tanhà – craving for mental impressions.
If we multiply the first group of 3 kinds of craving with thesecond group of 6, we get 18 kinds of craving. Again multiplying this by 2 as they can exist both internally and externally, we get 36 kinds of craving.
Now these 36 kinds of craving can occur in the past, in the present and in the future. So they total to 108 kinds of tanhà
May all beings be happy and well & attain Nibbana.