Welcome to Indian Hindu astrology. It has advanced techniques not yet found in Western or Chinese astrology. The following are some of the major differences:
There are many schools of thought in Indian Astrology. We follow one of the oldest, Maha Rishi Parasara Hora Shastra Vimshottari system.
Long before paper was invented, Indian Sages used zero and trigonometry. They used Sanskrit, a logically constructed language with words formed out of root sounds.
Without paper, all the calculations and predictions were converted into Sanskrit Songs. These slokas were learnt by heart. The teacher taught students to sing these slokas by repeating 100s of times.
Even today Hindus learn prayers and other Sanskrit slokas by repeating after the teacher. This starts at home where the mother teaches prayers to the small child. Indian prayers in Sanskrit have logical sound vibrations based on root sounds. They are not made of ordinary words like film songs. Hence Sanskrit prayers are effective.
Thousands of years ago ... Indian epics have horoscope details including Rahu and Ketu in them. These two are considered planets in Astrology. Actually they are the points where the moon's orbit intersects Earth's orbit around the Sun.
The moon's orbit is inclined slightly (by about 5 degrees) to the orbit of Earth's orbit around the sun. Hence the moon's orbit will intersect the plane of Earth's orbit at two points. These points are called Rahu and Ketu. This 3-D geometry was understood by ancient astronomers & astrologers as shown by the inclusion of Rahu and Ketu in the Ramayana (one of the 2 great epics of very ancient India).
The coming together of a scientific grammar for the Sanskrit language, the decimal system of numbers and the deep insight into time and how to mark it using astronomy led to a very sound base of knowledge since ancient times. This has been made use of by the royalty, the men in power and the general population to lead a more stress-free life. Even to this date the majority of the people in India take benefit from astrology and regulate events in life in accordance with this astrology.