In Palm Leaf Astrology, these palm leaves are catalogued as per the signs on the thumb print for Nadi palm leaf reading to reveal life predictions. For each thumb impression there are likely to be around five to six bundles; each such bundle in turn containing 50 to 100 leaves. The seeker's thumb print is used to approximately locate the closest bundle of leaves. "For Males the Right Hand Thumb Impression and for Females the Left Thumb Impression is Used" in Palm Leaf Astrology.

The use of Palm Leaf Astrology is different from other Hindu Vedic astrology system. As per Palm Leaf Astrology principles, the zodiac is divided in twelve equal sub-divisions of signs with equal subdivisions of the twenty-seven Nakshatras (constellations).

Further, these stars are subdivided into unequal sub Lords. Under Palm Leaf Astrology the sub lord is stronger than the Nakshatra and the Nakshatra is stronger than the planet. The sublords form the basis of Palm Leaf Astrology and which is based on the belief that the past, present and the future lives of all human beings were foreseen by Hindu sages (Saptarishi) in ancient times and written down as Palm Leaf Manuscripts which are mostly familiar in Vaitheeswaran koil, india.

On obtaining the aspirant thumb impression, it is handed over by the Palm Leaf Astrology reader at the library, as it is the scientific fact the whirls and loops of every individual is unique and it is next to impossible to be replicated. The thumb lines are classified into 108 types. The writings in palm leaf bundles are indexed and classified in the library according to thumb impressions to fascinate easy searching of the bundles. In Palm Leaf Astrology One particular leaf might be that of the individual, but the process of finding out that specific leaf is very laborious and time consuming.