Sandhyavandanam
Sandhyavandane (Sanskrit: संध्यावन्दन sandhyāvandana) is a mandatory religious ritual that needs to be performed by all twice-born people of Hinduism. Especially brahmins who are initiated into the sacred thread ceremony called as Upanayanam, and instructed in its execution by a Guru (a qualified spiritual teacher). Sandhyavandanam consists of excerpts from the Vedas that are to be performed thrice daily at morning (prātaḥsaṃdhyā), at noon (mādhyānika), and in the evening (sāyaṃsaṃdhyā).
The term is a Sanskrit compound consisting of saṃdhyā, meaning "union", or more specifically the union or junctions of day and night which takes place in the morning or evening twilight, and vandanam meaning worship. In addition to dawn and dusk, noon is considered the third juncture of the day, and hence meditations and prayers are performed daily at those times.
The term saṃdhyā is also used by itself in the sense of "daily practice" to refer to the performance of these devotions at the opening and closing of the day.
Read more about Sandhyavandanam: Sandhya Vandhana Is The Essence of Yoga & Meditation, Main Components of Sandhyavandanam, Daily Duties of Brahmins, Science Behind The Practice, Miscellaneous