Ismail Haji Omar, better known by his pen name, Noor S. I., is a Singapore-born Malay writer recognised as the pioneer of abstract Malay poetry. His most famous work, Senja (Dusk), is often cited by critics as one of the best pieces of poetry in the Malay-speaking world. In addition to poetry, Noor wrote drama scripts, essays and critiques. Some of the late poet's works were included in anthologies such as Bingkisan Angkatan Baru (1956), Puisi Bahara Melayu (1961), Himpunan Sajak (1969) and Orang Bertiga (1980). He was awarded the S.E.A. Write Award in 1985.

Noor S. I., whose real name was Ismail Haji Omar, was born in Singapore in 1933. He studied at Kota Raja Malay School until Primary Five and went to Arabic school thereafter for two years. Noor's first foray into the literary world was when he was 18. He joined three other youths, A. S. Amin, M. Ghazali and A. Samad Said to form Angkatan Sasterawan ’50 ( a literary movement of the ’50s). It was their goal to use poetry to improve society. During that period, Singapore was a hotbed of Malay literary activities, and the writers were the vanguard of the Malayan independence movement.

Noor's first poetry collection was published in the magazine, Samudera, when he was 18. In 1960, he had his collection of 50 poems, titled Setanggi Waja, published by the Malay Publishing House. The controversial volume was criticised for its unorthodox literary style. Noor's poems were full of symbolism, and reading the poems at face value made little sense. Critics who resented deviations from standard Malay poetry condemned Noor's work. They felt that it was an attempt to destroy the language. Because of this, Noor was given various nicknames that described his tendency to pen abstract poems, one of which was the label "penyajak kabur" or "vague poet".

Despite widespread criticism, Noor continued to write poems in an abstracted manner. He believed that poets were free to write in any form. As a poet in the politically charged years of the late 1950s, Noor said that writing helped shape his thinking. He told Berita Harian in an interview in 1985, "I must be prepared to enter the new era and contribute meaningfully to the new independence."

He contributed by sending poems to magazines, newspapers and literary journals that were willing to publish his works. In addition, his poetry was published in a number of anthologies, including Bingkisan Angkatan Baru (1956), Puisi Baharu Melayu (1961), Himpunan Sajak (1969), Titian Zaman (1979) and Orang Bertiga (1980).

As his body of work grew, Noor continued his involvement with Angkatan Sasterawan ’50, or ASAS ’50 as the literary group came to be known. He was a member of the group’s Poetry Reading Committee, helping to organise the society’s Chairil Anwar Night in 1957. He later became ASAS ’50’s Secretary from 1961 to 1976.

Noor's experimental poetry had its fair share of supporters. One of them was Datuk Hassan Ahmad, the former director of Malay Language and Literary Agency, better known as Dewan Bahasa dan Pustaka and a fellow "vague poet". He once said, "Poems which appear vague are on closer analysis so full of vitality and ideas that people should make the extra effort to understand them."

Malay language scholar, Dr Liaw Yock Fang, acknowledged Noor's poems as beautiful pieces, especially if read in the traditional way. Dr Liaw said, "His poems have a certain rhyme, with deep meanings that can be interpreted in many ways. They are steeped in symbolism, understood only by those familiar with his works."

By the late 1980s, Noor had written more than 500 poems and contributed to numerous anthologies. His collection of poetry includes Setanggi Waja, Rakaman Roh and Dewi Alam dan Bunga Senja. In addition to poetry, Noor published two anthologies of plays in 1974, Dayang Petani and Mana Bulan, Mana Bintang, and authored literary criticism essay, Sastera Melayu Singapore, Penulis dan Ketukangannya (Satu Pengalaman). In the late 1970s, he took on a position as an editor with book publisher Pustaka Nasional.

Noor received international recognition when he was awarded the S.E.A. Write Award in 1985 for his contributions to Southeast Asian literature. Today, his remain the most thought-provoking poems in the Malay-speaking region. Once derided for his abstract pieces, Noor is now thought of as one of the most celebrated poets in the contemporary literary scene. He passed away in November 1990 from complications arising from diabetes and kidney ailments. He is survived by his wife and three sons.