What is Tithi ?
A Tithi is the time taken for the longitudinal angle between the moon and the sun to increase by 12 degrees. A lunar month consists of 30 tithis, whose start time and duration vary.
Tithi plays an important role along with nakshatra in Hindus' daily as well as special activities in selecting the muhurta. There are auspicious tithis as well as inauspicious tithis, each considered more propitious for some purposes than for other.
What is Paksha ?
Paksha (or pakṣa: Sanskrit: पक्ष) refers to a fortnight or a lunar phase in a month of the Hindu lunar calendar.
A paksha has 15 tithis, which are calculated by a 12 degree motion of the Moon.
The first fortnight between New Moon Day and Full Moon Day is called "Gaura Paksha" or Shukla Paksha,
the period of the brightening moon (waxing moon), and the second fortnight of the month is called Krishna Paksha,
or "Vadhya Paksha", the period of the fading moon (waning moon).
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