Whether he is the best or not, I leave that to the critics. But as an ordinary lay reader, I consider him among one of my favorite writers hands down, if not for anything, just for creating Malgudi, and then his works like Swami And Friends, The English Teacher, The Bachelor of Arts, Financial Expert and Guide. Personally I would rate him as one of the shining lights of early Indian writing in English along with Raja Rao and Mulk Raj Anand.

Rasipuram Krishnaswamy Narayan aka R.K.Narayan, born in Chennai on October 10, 1906, grew up in Mysore, where he studied at the Maharaja High School. Nicknamed as Kunjappa, he was a voracious reader, who would often spend hours in the library. main influence was his grandmother, under whom he grew up, who taught him Math, Puranas, Sanskrit and classical music. . Among his literary influences were Thomas Hardy, Charles Dickens, Woodehouse, which reflected in his writing.
Graduating from the famed Mysore Maharaja College, he did struggle in getting his degree, working for some time as a teacher, before taking up writing as a full time career. It did not pay him much then, but was enough for a rather decent living.
Incidentally his first published work was a book review of Development of Maritime Laws in 17th century England. Swami and Friends was his first novel, based on his own childhood experiences, initially rejected by many publishers though.His uncle mocked Swami and Friends, and the book was rejected by a string of publishers. This was the book that created Malgudi, which was very much based on small town South India. I believe name was a mix of Malleswaram and Basavangudi as per some sources.
When he was in Coimbatore, R.K.Narayan fell in love with his neighbor Rajam and married her. He later became a reporter for The Justice, a Madras based newspaper, which bought him in touch with a larger circle of people.

It was Graham Greene who on reading Swami and Friends, recommended that it should be published, via Hamish Hamilton, a not so famous publisher. He also suggested R.K.Narayan to change the title, it's original one was Swam,the Tate. expressed his gratitude to Graham Greene, when he gifted a copy he told him "But for you, Swami wud be in bottom of Thames". They later became good friends.

The Dark Room, by R.K.Narayan was a pretty much serious take on domestic disharmony. Around the same time, his wife Rajam, whom he loved dearly passed away in 1939, just 6 years after they got married. This sent R.K.Narayan into a state of depression for some time, and his novel The English Teacher is based on this phase. He also set up a journal Indian Thought, which however folded up.
Mr. Sampath was more a comic realist novel, set in Malgudi, a satire on the movie and publishing world, that was also made into a movie. It was also the first of his works, that moved away from a semi autobiographical narrative, looking at other characters.The Financial Expert was one of R.K.Narayan's finest works, dealing with the rise and fall of it's protagonist Margayya. About a person who uses his intelligence to make money, but ends up having no peace of mind, a morality tale about excessive greed.
R K Narayan's next novel Waiting for the Mahatma, is again set in the backdrop of Gandhi's visit to Malgudi, and a romance woven around it. His classic novel The Guide was written when he was on a trip to the US, and it was set primarily in Malgudi.While the movie version of Guide was more or less faithful to the original novel, the backdrop in the movie was set in Rajasthan, also the book has a more open ending, where it's not known if Raju is alive or not, unlike in the movie.Man Eater of Malgudi published in 1961 was more a comic satire by R.K.Narayan, again the reference here is not to tigers or leopard, but rather the character of Vasu, an outsider who enters Malgudi, and annoys every one with his bullying, arrogant behavior.
Apart from his novels, R.K.Narayan also wrote Gods,Demons and Others, collection of short stories from Ramayan and Mahabharat. He covers stories of Yayati, Viswamitra, Ravan, Valmiki, Draupadi, Nala, Sibi Chakrvarty, in this book, worth a read
As per a promise made to his uncle, R K Narayan, began to translate the Kamba Ramayanam into English, that took 5 years and was published in 1973. He also wrote and published his version of Mahabharata too.
Asked by the Karnataka Govt to promote tourism, R.K.Narayan came up with the Emerald Route,a superb travelogue that looks at the state's rich heritage, history, culture and nature. A wonderful first person look at the state, as he explores it from from Bangalore to Bellary to Halebid.
He was a truly versatile writer- fiction, short stories, travelogues and Puranas, covered all genres well. He even tried his hand at farming, bought an acre of agricultural land near Mysore. He loved talking walks, interacting with people at the market place, in fact most of his books were based on his interactions with people around him.
One of the few people from outside the political community who made a significant impact in Rajya Sabha was R.K.Narayan. The Yash Pal committee for educational reforms was established after his speech on the burden on school kids. Of R.K.Narayan's later novels A Tiger for Malgudi is about a tiger narrating it's experiences in captivity. He also wrote A Writer's Nightmare about various social issues in India. And Under the Banyan Tree, a collection of short stories.
More than anything else, R.K.Narayan, bought English writing to the average Indian with his very simple language and narrative. And above all he would forever be remembered for Malgudi, the fictional town, reminiscient of every small town in the South.
Very well written article about RKN sir! Thanks for this :)