Vishnu Sahasranam is one of the most sacred and chanted stotra by Hindus. Recited daily by many Vaishnavites, devotees of Lord Vishnu, Vishnu Sahasranama contains a list of thousand name of Lord Vishnu, a premier Hindu deity (the other two in trilogy are Shiva and Brahma). Just as Bhagavad Gita, Vishnu Sahasranam is also part and parcel of Mahabharat. It is found in the Anushasana Parva, Section 149, verses 14 to 120. The Sahasranama (apart from the initial and concluding prayers) has a total of 108 shlokas in Anushtup chhanda (a meter of poetry).
Vishnu Sahasranama is another masterpiece from Sage Vyasa, an extraordinary Sanskrit scholar and author of many timeless classics such as Mahabharata, Bhagavad Gita, Puranas and various Stotras. Vishnu Sahasranam has been the subject of numerous commentaries, the most popular being one written by Adi Shankaracharya.
In Sanskrit, 'sahasra' means 'a thousand' and 'nāma' means 'name'. The compound 'Sahasranam' (or 'Sahasranama') may be translated as 'having thousand names'. Thus, Vishnu Sahasranama literally means Lord Vishnu with thousand names or thousand names of Lord Vishnu. In modern Hindi, it is pronounced as Sahasranām while in South Indian languages, it is pronounced as Sahasranāmam. There are Sahasranāma for major forms of God (Vishnu, Shiva, Shakti, and others), but Vishnu Sahasranāma is most popular among common people. The other Sahasranamas are recited mostly in temples or by learned and scholars.
It is interesting to know the history behind Vishnu Sahasranama. On the battlefield of Kurukshetra, Bhisma - the great grandfather of Kauravas and Pandavas was lying on his deathbed. With Bhishma's death, an era of great wisdom and knowledge was about to come to an end. There for, Lord Krishna advised Yudhisthir to seek Bhishma's counsel on any and all aspects of life. The dialogue, which was witnessed by Sage Vyasa and Lord Krishna as well, reflects essence of Bhishma's life. During the dialogue, in response to Yudhisthir's questions such as Who is the ultimate Supreme reality of the creation; by worshipping whom a man attains salvation; and what is the easiest way by which mankind can get everlasting happiness, eternal peace and become free from misery and sorrow, Bhishma mentioned thousand names of Lord Vishnu.
It is true that the charm and magnetism of this Stotra can only be felt completely in Sanskrit, but not many people study it these days. For Gujarati people, Shri Yogeshwarji translated this stotra in poem form in 1953. It was later published in a book form during sixties. Thereafter due to popular demand, it has been reprinted more than six times.