The Sadhu...

In Hinduism, sadhu is a common term for an ascetic or practitioner of yoga (yogi) who has given up pursuit of the first three Hindu goals of life: kama (pleasure), artha (wealth and power) and even dharma (duty). The sadhu is solely dedicated to achieving moksha (liberation) through meditation and contemplation of God.

Sadhus are often sanyasi, or renunciates, who have left behind all material and sexual attachments and live in caves, forests and temples all over India. The word comes from the Sanskrit "to practice", referring to the practice of meditation. See sadhana.
A sadhu is usually referred to as baba by common people. The word 'baba' means father, or uncle, in most Indian languages. Sometimes the respectful suffix 'ji' may also be added after baba, to give greater respect to the renunciant. There are 4 or 5 million sadhus in India today and they are still widely respected, revered and even feared, especially for their curses. It is also thought that the austere practices of the sadhus help to burn off their karma and that of the community at large. Refer...