who was this last person?
He is celebrated as the harbinger-poet in Sanskrit literature.
Valmiki
Valmiki (; Sanskrit: वाल्मीकि , "Vālmīki"), also known as Lal Beg or Bala Shah, is celebrated as the harbinger-poet in Sanskrit literature. 
what is the relation between kuber and ravan in mythology Kubera is described as the uncle of Ravana in the "Mahabharata". what is this former one worshipped for? He is worshipped as the god of wealth. what significance it has in other religion? In Jainism, he is the attendant Yaksha of the 19th Tirthankar Mallinath. is he a good deity according to the puranas? Yes, as The "Purana"s grant him unquestioned godhood. who is the above mentioned latter god? A king of Lanka and the chief antagonist in the Hindu epic "Ramayana" and its adaptations. where was he born? There are several beliefs, but the people of Bisrakh village in Uttar Pradesh claim that Bisrakh was named after Vishrava, and that Ravana was born there. is he a follower of lord shiva? Yes how is he related to linguistics? He is the composer of the "Ravanabhet" and "Ravaniya". and any medical connection? He is also the composer of the 16th century C.E. scriptures "Nadi Pariksa" and "Nadi Vijnana" on knowledge about the veins. what service did he provide to lord vishnu? As gatekeeper at Vaikuntha. what is this last thing you mentioned just now? It  is the celestial abode (dwelling) of Vishnu. who is the composer of the above mentioned hindu epic? It is traditionally ascribed to the Maharishi Valmiki.
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Valmiki [SEP] Introduction
Valmiki (; Sanskrit: वाल्मीकि , "Vālmīki"), also known as Lal Beg or Bala Shah, is celebrated as the harbinger-poet in Sanskrit literature. The epic "Ramayana", dated variously from the 5th century BCE to first century BCE, is attributed to him, based on the attribution in the text itself. He is revered as "Ādi Kavi", the first poet, author of "Ramayana", the first epic poem. The "Ramayana", originally written by Valmiki, consists of 24,000 shlokas and seven cantos (kaṇḍas). The is composed of about 480,002 words, being a quarter of the length of the full text of the "Mahabharata" or about four times the length of the "Iliad".