My Sun is in Capricorn on Western sites and in Sagittarius in my Vedic chart. For years that annoyed me until an older astrologer said: stop arguing with the calendar and ask what each luminary does. The Sun is visibility. The Moon is experience.
Chandra as manas
In Sanskrit texts, the Moon governs the mind's texture: memory, mood, receptivity, the way you digest both food and emotion. That is why Panchang, muhurat, and fasts track lunar days. The Moon moves quickly, so it describes what changes within you week to week.
Your Moon sign (Rashi) and Moon nakshatra (birth star) anchor Dasha systems, compatibility, and many remedial suggestions. Sun sign descriptions can feel flattering but vague. Moon sign readings often feel uncomfortably specific. That specificity is the point.
Practical differences you can notice
Track your mood against the Moon's transit through your chart for one month. Not as superstition, as observation. Many people find their sleep, appetite, or sensitivity shifts when the Moon crosses their eighth house or conjoins Saturn. You do not need to fear it. You can plan lighter days.
Sun sign: how you want to be seen. Moon sign: what you need to feel safe.
If you only know your Western Sun sign, generate a sidereal chart with accurate birth time. Read the Moon first. Then the ascendant (Lagna). The Sun comes third for daily life, even though it remains vital for career and authority themes.