Calendar System

Hindu calendar is lunar based, i.e, it depends on the phases of the moon. In it, the day starts with local sunrise. It is allotted five "properties", called angas. They are:
  • the tithi (one of 30 divisions of a synodic month) active at sunrise
  • the vaasara, vaar (ravi-vaar, som-vaar, etc.) or weekday
  • the nakshatra (one of 27 divisions of the celestial ecliptic) in which the moon resides at sunrise
  • the yoga (one of 27 divisions based on the ecliptic longitude of the sun and moon) active at sunrise
  • the karana (divisions based on tithis) active at sunrise.
Together these are called the panchāngas.

Rashi
 It is the one of the 12 zodiac constellation. All the objects of the solar system pass through these. There are twelve rāshi names, there are twelve lunar month names. When the sun transits into the Mesha rāshi in a lunar month, then the name of the lunar month is Chaitra. When the sun transits into Vrishabha, then the lunar month is Vaishākh. So on.
Aries
Taurus
Gemini
Cancer
Leo
Virgo
Libra
Scorpio
Sagittarius
Capricorn
Aquarius
Pisces

Tithi: A lunar day. Named in sanskrit, amavasya and purnima and prathama, dvitiya, etc . As tithi changes the phase of the moon also changes

Paksha: A lunar month is divided in two pakshas.
  • Shukla paksha: size of moon increases. Tithi changes from Amavasya to Purnima.  Waxing phase.
  • Krishna paksha: size of the moon decreases.  Tithi goes from Purnima to Amavasya.  Waning Phase.
Months

  1. चैत्र Chaitra
  2. वैशाख Vaisakha
  3. ज्येष्ठ Jyaishtha
  4. आषाढ Ashadha
  5. श्रावण Sravana
  6. भाद्रपद Bhadrapada
  7. आश्विन Asvina
  8. कार्तिक Kartika
  9. मार्गशीर्ष Margasirsha
  10. पौष Pausha
  11. माघ Magha
  12. फाल्गुन Phalguna
Vaar

  1. रविवार Ravivara
  2. सोमवार Somavara
  3. मंगलवार Mangalavara
  4. बुधवार Buddhavara
  5. गुरुवार Brihaspatvara
  6. शुक्रवार Sukravara
  7. शनिवार Sanivara

Nakshatra
  1. अश्विनी Aswini
  2. भरणी Bharani
  3. कृत्तिका Kritika
  4. रोहिणी Rohini
  5. म्रृगशीर्षा Mrigasira
  6. आद्रा Aridra
  7. पुनर्वसु Punarvasu
  8. पुष्य Pushya
  9. आश्लेषा Aslesha
  10. मघा Magha
  11. पूर्व फाल्गुनी Poorvaphalguni
  12. उत्तर फाल्गुनी Uttaraphalguni
  13. हस्त Hasta
  14. चित्रा Chitra
  15. स्वाती Swati
  16. विशाखा Visakha
  17. अनुराधा Anuradha
  18. ज्येष्ठा Jyehsta
  19. मूल Moola
  20. पूर्वाषाढा Poorvashadha
  21. उत्तराषाढा Uttarashadha
  22. श्रवण Sravana
  23. धनिष्ठा Dhanshita
  24. शतभिषक् Satabisha
  25. पूर्वभाद्रपदा Poorvabhadrapada
  26. उत्तरभाद्रपदा Uttarabhadrapada
  27. रेवती Revati
Yoga
  1. Vishkambha
  2. Priti
  3. Ayushman
  4. Saubhagya
  5. Sobhana
  6. Atiganda
  7. Sukarma
  8. Dhriti
  9. Soola
  10. Ganda
  11. Vriddha
  12. Dhruva
  13. Vyagatha
  14. Harshana
  15. Vajra
  16. Siddhi
  17. Vyatapata
  18. Variyan
  19. Parigha
  20. Siva
  21. Siddha
  22. Sadhya
  23. Subha
  24. Sukla
  25. Brahma
  26. Indra
  27. Vaidhriti
Karana
  • Kinstughna, Bhava, Balava, Kaulava, Taitula, Garaja, Vanija, Visti (Bhadra), Sakuni, Catuspada, Nagava