«The Kama Sutra» by Vatsyayana

The Kama Sutra is widely considered to be the standard work on human sexual behaviour in Sanskrit literature. A portion of the work consists of practical advice on sexual intercourse. It is largely in prose, with many inserted anustubh poetry verses. "Kāma" which is one of the four goals of Hindu life, means desire including sexual desire the latter being the subject of the textbook, and "sūtra" literally means a thread or line that holds things together, and more metaphorically refers to an aphorism (or line, rule, formula), or a collection of such aphorisms in the form of a manual.
Contrary to western popular perception, the Kama Sutra is not exclusively a sex manual; it presents itself as a guide to a virtuous and gracious living that discusses the nature of love, family life and other aspects pertaining to pleasure oriented faculties of human life. Kama Sutra, in parts of the world, is presumed or depicted as a synonym for creative sexual positions. The majority of the book is about the philosophy and theory of love, what triggers desire, what sustains it, how and when it is good or bad. The Kama Sutra is the oldest and most notable of a group of texts known generically as Kama Shastra.