Early Persians wore a conical cap sometimes encircled by bands of cloth, which may be considered one of the origins of the modern turban. The turban didn't become common among the Turks, but was common among the Ottoman sultans.
Turban's shape, size and color varies and the cloth's length could be even 45 meters. In some ares, especially in Rajasthan the turban's size could indicate the position of the person in society.
In India name of the turban is a pagdi. There exists different variations of the headdress, depending on the region and religion. In fact, in Rajasthan it is said that the style of the turban changes with every 15 km you travel. Other thing is that Rajput turbans are different from Sikh turbans, which are in turn different from the classical Arab turbans. There are also royal turbans from different parts of India and the rural version of turban which is often just a towel wound round the head.