Free astrology
Hindu and Western astrology - Palakkad
The most easily referred to difference between the two lies in the method of measurement of the Zodiac. Vedic astrology uses primarily the sidereal zodiac (in which stars are considered to be the fixed background against which the motion of the planets is measured), whereas most Western astrology uses the tropical zodiac (the motion of the planets is measured against the position of the Sun on the Spring equinox). Of course, the ancient rishis were aware of the tropical, season-based cycles of northern and southern declination paths of the Sun and used them also when appropriate. But in the popular mind, the main difference between the two systems is that Jyotish uses the sidereal zodiac and Western astrology uses the tropical. The most obvious effect of the sidereal/tropical difference is that about 80% of planets in a Western chart will move to the previous sign in a sidereal reading of the same chart.

Both Jyotish and Western traditions have existed for millennia. Vedic astrology includes several nuanced sub-systems of interpretation and prediction incorporating unique sacralized elements not found elsewhere, such as its specific system of lunar mansions (called nakshatras, encompassing a pantheon of archetypal deities). The nakshatras are used to pick auspicious times of day or month for every human activity as well as to provide insight into the motivations and guiding characteristics of humans and events coming under their influence. Nakshatra cycles, or dashas, are developing a reputation in contemporary culture for the accuracy with which they time events.
A further unique concept in jyotish not seen in Western astrology is the concept of Dashas - a mathematical analyses that breaks down human or the subject's lifetime into various sub-periods based on the location of Moon at birth.
Predictions in jyotish incorporate various elements around the birth chart - influences of transits (similar to Western Astrology though more focused on houses or bhavas) as well as Dashas