In Jainism, "tap" refers to austerities or spiritual practices undertaken to purify the soul and progress on the path of liberation (moksha). There are several types of "tap" (tapasya), which are broadly classified into two categories: Bahyatapa (external austerities) and Antaratapa (internal austerities). Some examples of tap include:

External Tapas (Bahyatapa):

1. Anashana (Fasting)
2. Unodari (Eating less than one’s appetite)
3. Vritti-sankshepa (Limiting the number of food items)
4. Rasa-parityaga (Renouncing tasty foods)
5. Kaya-klesha (Physical endurance)
6. Sanlinata (Solitude and meditation)

Internal Tapas (Antaratapa):

1. Prayaschitta (Repentance)
2. Vinaya (Humility)
3. Vaiyavritya (Selfless service)
4. Swadhyaya (Scriptural study)
5. Vyutsarga (Renunciation)
6. Dhyana (Meditation)

Regarding "river," in Jain cosmology and literature, rivers are often mentioned in the context of geography or as pilgrimage sites, but there is no particular river that is central to Jain doctrine as in some other faiths. However, many Jain pilgrimage sites (tirthas) are located near rivers or water bodies. The word "tirtha" itself means "ford" or "crossing place," symbolizing a spiritual crossing over the cycle of birth and death, but it does not refer to a specific river.

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