[2] He is nicknamed "Isaignani" (the musical sage) and is often referred to as "Maestro", the title conferred to him by the Royal Philharmonic Orchestra, London.

[7] In 2013, when CNN-IBN conducted a poll to commemorate 100 years of Indian cinema, he secured 49% of the vote and was adjudged the country's greatest music composer.

[12] Ilaiyaraaja was born as Gnanathesigan in a Dalit family in Pannaipuram in present-day Theni district, Tamil Nadu, India, on 3 June 1943.

[13][14] At the time of joining school, his father, Daniel Ramasamy[15] changed his name from Gnanathesigan[16] to "Rajaiya", and the people in his village called him "Raasayya".

[21] While working with the troupe, he penned his first composition, a musical adaptation of an elegy written by the Tamil poet laureate, Kannadasan, for India's first prime minister, Jawaharlal Nehru.

[18] The course included an overview of Western classical music, compositional training in techniques such as counterpoint, and study in instrumental performance.

Ilaiyaraaja was a gold medalist in classical guitar after completing the course through a distance-learning channel from Trinity College of Music, London.

[21][26][27] During the 1970s in Chennai, Ilaiyaraaja played guitar in a band-for-hire, and worked as a session guitarist, keyboardist, and organist for film music composers and directors such as Salil Chowdhury from West Bengal.

[41] He worked with Indian poets and lyricists such as Kannadasan, Vaali, Vairamuthu, O. N. V. Kurup, Sreekumaran Thampi, Veturi, Acharya Aatreya, Sirivennela Seetharama Sastry, Chi.

[43] Cinematographer Santosh Sivan said that Ilaiyaraaja finished composing for the entire soundtrack of the film Thalapathi in less than "half a day".

[48] The second, Nothing But Wind (1988), was performed by flautist Hariprasad Chaurasia and a 50-piece orchestra and takes the conceptual approach suggested in the title—that music is a "natural phenomenon akin to various forms of air currents".

[49] He has composed a set of Carnatic kritis which were recorded by electric mandolinist U. Srinivas for the album Ilayaraaja's Classicals on the Mandolin (1994).

[57] Ilaiyaraaja's song 'Naanthaan Ungappanda' from the 1981 film Ram Lakshman was part of the playlist for the opening ceremony of the 2012 Summer Olympics.

[58][59] His compositions Paayum Puli Title Music and Ilamai Itho were part of the soundtrack of Ashim Ahluwalia's 2012 Cannes Film Festival entry, Miss Lovely.

[60] The Lovebirds (2020) incorporated a section of Ilaiyaraaja's "Oru kili" soundtrack composed for the movie Aanandha Kummi (1983) as background music in its official trailer.

His first major live performance since his debut was a four-hour concert held at the Jawaharlal Nehru Indoor Stadium in Chennai, India, on 16 October 2005.

On 5 September 2012, Ilayaraja performed in a live concert in Chennai with the Hungarian National Philharmonic orchestra; during this event the music launch of his films Neethaane En Ponvasantham and Yeto Vellipoyindhi Manasu took place.

[71] The Toronto concert was promoted by Trinity Events for Vijay TV in India and produced by Sandy Audio Visual SAV Productions with PA+.

Following his show at Toronto, Ilaiyaraaja also performed at the Prudential Center Newark, New Jersey, on 23 February 2013 and at the HP Pavilion at San Jose on 1 March 2013.

When enquired if it was mystical as in the case of mathematical genius Srinivasa Ramanujan, who insisted he received math formula in dreams from a goddess, Ilaiyaraaja said that unlike Ramanujan who felt a supernatural being guiding him, he always felt a moment of clarity when a composition came to his mind—"It is as if I am the subject and the object of art at the same time when that happens," he said.

He uses electronic music technology that integrates synthesizers, electric guitars and keyboards, drum machines, rhythm boxes and MIDI with large orchestras that feature traditional instruments such as the veena, venu, nadaswaram, dholak, mridangam and tabla as well as Western lead instruments such as saxophones and flutes.

The melodic structure of his songs demand considerable vocal virtuosity, and have found expressive platform amongst some of India's respected vocalists and playback singers, such as T. M. Soundararajan, S. Janaki, P. Susheela, K. J. Yesudas, K. S. Chithra, S. P. Balasubrahmanyam, M. G. Sreekumar, Rajkumar, Asha Bhosle, Lata Mangeshkar, Jayachandran, Uma Ramanan, S. P. Sailaja, Jency, Swarnalatha, Minmini, Sujatha, Malaysia Vasudevan, Kavita Krishnamurti, Hariharan, Suresh Wadkar, Udit Narayan, Sadhana Sargam and Shreya Ghoshal.

[79] Although Ilaiyaraaja uses a range of complex compositional techniques, he often sketches out the basic melodic ideas for films in a very spontaneous fashion.

[80] Prime Minister Narendra Modi conferred an honorary doctorate to Ilaiyaraaja during the 36th Convocation Ceremony of Gandhigram Rural Institute in Tamil Nadu's Dindigul.

[83][84] In 2012, he received the Sangeet Natak Akademi Award, the highest Indian recognition given to practising artists, for his creative and experimental works in the music field.

[86] In 2003, according to an international poll conducted by BBC of more than half-a million people from 165 countries, his composition "Rakkamma Kaiya Thattu" from Thalapathi was voted fourth in the top 10 most popular songs of all time.

[7] Achille Forler, board member of the Indian Performing Right Society, said in 2017, "the kind of stellar body of work that Ilaiyaraaja has created in the last 40 years should have placed him among the world's top 10 richest composers, somewhere between Andrew Lloyd Webber ($1.2 billion) and Mick Jagger (over $300 million).

[95] On 6 July 2022, Ilaiyaraaja was nominated to the Rajya Sabha as Member of Parliament by the President of India, Ram Nath Kovind.

[99] His brother, Gangai Amaran, is also a music director and lyricist in the Tamil film industry,[100] and both were not on talking terms for 13 years until they met in February 2022.

"[107] In April 2022, Ilaiyaraaja triggered a controversy by writing a foreword in the book titled, "Ambedkar & Modi—Reformer's Ideas", in which he praised the Prime Minister Narendra Modi and compared him to B.R.