The foundation of Hindu astrology is the notion of bandhu of the Vedas (scriptures), which is the connection between the microcosm and the macrocosm. Practice relies primarily on the sidereal zodiac, which is different from the tropical zodiac used in Western (Hellenistic) astrology in that an ayanamsa adjustment is made for the gradual precession of the vernal equinox.
Hindu astrology includes several nuanced sub-systems of interpretation
and prediction with elements not found in Hellenistic astrology, such as its system of lunar mansions (nakshatras).
Some of the important elements used to arrive at predictions include:Natal birth chart,Divisional Charts,Vimshottari Mahadashas,Chara Dashas,etc.

The great seers (maharishis) recorded the destiny of individual souls [jivas] for all time. They did this by cognizing the subtle mechanics of creation on the finest levels of their own awareness. These cognitions were recorded in the form of a dialogue between lordshiva  his consort durgaa In other words, through the perfect refinement of their awareness these enlightened sages directly experienced or ‘heard’ the self interacting dynamics of pure consciousness: the absolute field of existence. In this eternal conversation, God whispers to Himself about you – the details of your life & your future

These akashic records were written on palm leaves with an iron stylus. The leaves are collected in bundles. The bundles containing these palm leaf records were handed down through generations. Over the years the collections have been retranslated, scattered and recollected.

Nadi Jothidam is the name of an ‘exact science’ by which all details about a person can be told by consulting palm-leaf inscriptions attributed to Agastya Muni, a very famous ancient sage from the South. There is, supposedly, one palm-leaf inscription for every human on this earth, past present and future! Taking into account population explosion, the whole place should be chock full of palm leaves, but miraculously this is not so. This could mean two things- either the ancients had the foresight to know as to who would visit the place and hence only the bio-data of those visitors would be available,or the leaves are preserved in some format wherein terabytes of data could be compressed and stored. The prints would be taken after the candidate arrives on the spot!

Either way it goes to show the remarkable wisdom of our ancients! Anyway, after one arrives at the place their thumb impression is taken along with their date of birth. Then, the palm leaf pertaining to the individual is searched for. This is the source of the name Nadi- search. There are a number of write-ups praising its accuracy and there are blogs testifying to the same. There have been numerous accounts stating that the practitioners of Nadi have an accurate method of telling all about the past, present and future of any individual. All they need for identifying the right leaf is the thumb-print of the person and the date of birth.