The word Rāvaṇa (Sanskrit: रावण) means "Roaring" (active), the opposite of Vaiśravaṇa which means to "hear distinctly" (passive). Both Ravana and Vaiśravaṇa, who is commonly known as Kubera, are considered to be patronymics derived from "sons of Vishrava".

Ravana was a title later taken on by Dashānana, and it means "the one with ten (dasha) faces (anana)". Further, roravana is Sanskrit for "loud roaring." In Abhinava Gupta's Krama Shaiva scripture, yāsām rāvanam is used as an expression to mean people who are truly aware of the materialism of their environment.

Ravana has many other popular names such as Dasis Ravana, Dasis Sakvithi Maha Ravana, Dashaanan, Ravula, Lankapati, Lankeshwar, Lankeshwaran, Ravanasura and Ravanaeshwaran.

Ravana is depicted and described as having ten heads, although he is sometimes shown with only nine heads since he cut one off to convince Shiva. He is described as a devout follower of Shiva, a great scholar, a capable ruler, and a maestro of the Veena. Ravana is also depicted as the author of the Ravana Samhita, a book on Hindu astrology, and the Arka Prakasham, a book on Siddha medicine and treatment. Ravana possessed a thorough knowledge of Siddha and political science. In some later versions, he is said to have possessed the nectar of immortality, which was stored inside his belly thanks to a celestial boon from Brahma. In the War with Lord Rama, Ravana was killed by a powerful Brahma's weapon shot by Rama which was gifted to Rama by Sage Agstya.

In the Bhagavata Purana, Ravana and his brother Kumbhakarna are said to be reincarnations of Jaya and Vijaya, gatekeepers at Vaikuntha (the abode of Vishnu), and were cursed to be born on Earth for their insolence.

These gatekeepers refused entry to the Sanatha Kumara monks who, because of their powers and austerity, appeared as young children. For their insolence, the monks cursed them to be expelled from Vaikuntha and to be born on Earth.

Vishnu agreed that they should be punished and gave them two options. First, that they could be born seven times as normal mortals and devotees of Vishnu, or be born three times as strong and powerful beings, but as enemies of Vishnu. Eager to be back with the Lord, they chose the latter option. The curse of the first birth was fulfilled by Hiranyakashipu and his brother Hiranyaksha in Satya Yuga, when they were both vanquished by earlier avatars of Vishnu (Hiranyaksha by Varaha, and Hiranyakashipu by Narasimha). Ravana and his brother Kumbhakarna were born to fulfill the curse in their second birth as enemies of Vishnu in Treta Yuga. The curse of the third birth was fulfilled by Dantavakra and Shishupala in the Dvapara Yuga, when they both were slain by Krishna, the eighth avatar.
Ravana had fought with the demons named Nivatakavacha along with his army for an entire year but was unable to kill them due to Brahma's boon. The war was stopped by Brahma and Ravana formed an alliance with them, he learnt several magical tricks or maya from those demons.

Ravana had defeated the vanara warriors namely Hanuman, Sugriva, Neela and even Rama's brother Lakshmana twice during his war with Rama. As per the original six books of Valmiki Ramayana, only lord Rama the incarnation of Vishnu defeated Ravana and killed him after several days of single duel.

Once, upon hearing a discourse from Sage Sanatkumara, Ravana attempted to invade Vaikuntha. Only Ravana managed to enter Vaikuntha's capital, Shwetadwipa, where he was hopelessly outmatched by the inhabitants and was forced to retreat.

He killed Anaranya, the king of Ayodhya, although he cursed Ravana to be slain by Rama.

Ravana had wrestled his brother Kubera and vanquished him for the Pushpaka Vimana.

He also fought Marutta (Chakravarti King of Ushiraviga), Gadhi (Vishwamitra's father), Dushyanta (Bharata's father), Suratha (King of Vidarbha), Gaya (Chakravarti king of Dharmaranya), and Paurava (King of Anga).
Ravana is regarded to have once caught sight of the apsara Rambha and was filled with lust. Even as the apsara resisted his advances by asserting that she was his daughter-in-law, he raped her. When she reported this to her husband, Nalakuvara, he cursed Ravana to be unable to cause violence to any woman who did not consent to being with him, his head splitting into a number of pieces if he did so. This incident is stated to explain why Ravana could not force the abducted Sita to submit to his desire.

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