The six vedangas are 1) phonetics or shiksha, 2) prosody or chhandhas, 3) grammar or vyakarana, 4) etymology or nirukta, 5) astronomy or jyotisha and 6) rituals or kalpa. The first one shiksha consists of correct pronunciation and intonation. Stress on the correct word was important which otherwise would lead to different interpretation. Letter of alphabet (varna), measure of time (mantra), stress (bala) and sama or correct juxtaposition formed the ingredients of shiksha.
The Chhandhas or the second anga is meter in poetry or vedic chanting. It starts with paying respect to the sage of whom that particular mantra was revealed and the God of whom the mantra is addressed, as also the meter in which it is composed. Gayatri, anushthuh and jagati are famous meters of vedic times. Over centuries chhandas developed into shastra (science) which played a key role in classical Sanskrit.
Grammar or vyakarana formed the essential part of vedanga, that helped to interpret technical terms and statements of rituals. Agamas are Vedic statements, which help clear doubts as most of this hoary literature was preserved in aphorisms or sutras. Vedic vyakarana tried to bring out real purport of Vedic literature. Panini the greatest grammarian, names some grammarians who preceded him.
Nirukta is commentary on nighantu or lexicon of Vedic terms, in most ancient times. Yashka the author of Nirukta perhaps lived in 1000 BC, though Hindu tradition takes him back by another millennium. His is the earliest commentary on vedic terminology. All words according to Yashka, are derived from dhatu or verbal roots and mantras have specific meaning and usage, as also ways of deriving. Nirukta is highly scientific and systematic, which paved the way later for the development of classical Sanskrit. Today Sanskrit is one ancient language which renders itself beautifully to computerization.
The Jyotisha is astronomy and India excelled in it. Greek and Arab scholars came to India in ancient and medieval times and Alberuni was one of them, who has left a valuable information of education in Sanskrit and astronomy in particular over which he toiled for six years. In the earliest stage, astronomy was a science of luminary cosmic objects, which were believed to have unseen but predictable effects on human lives. Auspicious moments were also to be calculated for performing sacrifices.
The sixth or last limb of veda is kalpa. Originally it was formed to help with practical suggestions in conducting various sacrifices, including construction of altars. In later times kalpa came to denote time-measurement. Brahma, the creator of cosmos is supposed to have one day in his life equal to one kalpa. In terms of human years, one kalpa is 4.32 billion years. Yugas, manvantras (eras) and chakras (cycles) form other measurement of time.
