The time between two new moons is called 'lunar month' and it is equivalent to about 30 days. There are 30 tithis or lunar days in a lunar month. We can also understand Tithi in such a way that the time it takes for the 'Moon line' to move 12 degrees above the 'Sun line' is
called Tithi.
Therefore there are a total of fourteen Tithis between each new moon and full moon. The 'zero' is called the new moon and the fifteenth date is called 'purnima'. Tithi’s mean 'zero', starting from the new moon to the full moon, and then starting from the full moon and completing the same sequence again till the new moon, then a lunar month is completed.
Total Tithi’s and its count
According to the Hindu calendar, there are 30 Tithis in the month, which are divided into two
Pakshas: Shukla Paksha and Krishna Paksha respectively.
Names of Tithi’s
◉ Amavasya (New Moon Day)
◉ Pratipada
◉ Tritiya
◉ Chaturthi
◉ Panchami
◉ Shashti
◉ Saptami
◉ Ashtami
◉ Navamii
◉ Dashmi
◉ Ekadashi
◉ Twadashi
◉ Trayodashi
◉ Chaturdashi
Poornima (full moon day) or Poornamasi
Adhyatmik Ganana
All tithi’s have their own spiritual characteristics like -
◉ Amavasya is ideal for 'Pitru Puja'.
◉ Chaturthi is ideal for worshiping Ganpati.
◉ Panchami is ideal for worshiping Adishakti.
◉ Shashti is ideal for 'Kartikeya Puja'.
◉ The worship of Navami 'Ram' is ideal.
◉ Ekadashi and Dwadashi are ideal for worshiping Vishnu.
◉ Trayodashi is ideal for Shiva worship.
◉ Chaturdashi is ideal for worshiping Shiva and Ganesha.
Purnima is good for all kinds of worship-related activities.