Long ago the Ancients realized that how a planet expresses its energy depends on what sector of the Heavens it is situated in. The need for describing the positions of the planets amongst the stars is what gave rise to the system of Astrological Signs. It may come as a surprise to learn that there is more than one way to divide up the Heavens into signs. By employing more than one zodiac, we can derive more details and gain more insight into how a planet operates in an astrology chart.

In Vedic Astrology, alongside, or parallel to, the 12-sign solar zodiac, there is another system of 27 signs, based on the path of the Moon. These signs are called the Nakshatras. Increasing the number of signs to 27 provides more differentiation between sectors of the Heavens, with the potential of more specifics, leading to a more accurate delineation of any chart factor under consideration. Each nakshatra comprises 13 deg, 20 min, of the zodiac (as compared to 30 deg for each solar sign). Understanding the meanings of the nakshatras that are featured in your own chart puts you more in touch with the particular part of the cosmic energy pattern that you are born to manifest. That’s why I like to include them when doing a birth chart reading.

The nakshatra system adds another dimension to chart interpretation by way of its connection with Hindu mythology. The ancients identified the stars and planets with gods, and constructed stories to explain their relationships. These stories serve as archetypes of the many variations of human nature. Each nakshatra has a Hindu deity or mythological character, sometimes more than one, associated with it. The nature of that mythological entity tells us something about the condition of any planet in a natal chart that is posited in that nakshatra.

Since the Moon changes to a new nakshatra every day, the nakshatra system plays a big part in another technique of Vedic Astrology: Muhurta. This is the method used by the astrologer to choose the best day for commencing an important action. The idea being that you want to choose a day when the energy is appropriate to the action that you are planning to initiate. Some nakshatras are good for creative acts, others are good for defeating enemies, still others are preferred for travel, or for beginning studies or religious initiations.

Traditionally, the nakshatra of your natal Moon is considered the most important. It is called your “Janma Nakshatra,” which is translated as “Birth Star.” In traditional India, instead of asking “ what is your sign?” you are asked “what is your birth star?” The sound associated with your janma nakshatra is used as the basis of your first name. For marriage, the janma nakshatra is all important. There’s a whole system of compatibility astrology based on the qualities of the janma nakshatras of the prospective partners.

To list all the nakshatras and their characteristics with associated Hindu myths requires a whole book. Here are two that I like, the first is a simple introduction, the second is much more comprehensive:
The Nakshatras by Dennis Harness The 27 Celestial Portals by Prash Trivedi