Sahib Sri Guru Granth Sahib ji

Sri Guru Granth Sahib is the holy book of the Sikhs. The Sikhs treat this Granth (holy book) as a living Guru. The holy text spans 1430 pages and contains the actual words spoken by the founders of the Sikh religion (six Sikh Gurus) and the words of various other Saints from other religions including Hinduism and Islam.
Guru Gobind Singh Ji, the tenth master, in 1708 established Guru Granth Sahib as the eternal Guru of the Sikhs. Guru Gobind Singh said before his demise that the Sikhs were to treat the Granth Sahib as their next Guru. Guru Ji said – “Sab Sikhan ko hukam hai Guru Manyo Granth” meaning “All Sikhs are commanded to take the Granth as Guru” So today if asked, the Sikhs will tell you that they have a total of 11 Gurus (10 in human form and the SGGS).
When one visits a Gurdwara (a Sikh temple), the Guru Granth Sahib forms the main part of the Darbar Sahib or Main Hall. The holy book is placed on a dominant platform and covered in a very beautiful and attractively coloured fine cloth. The platform is always covered by a canopy, which is also decorated in a very attractive coloured material. The text in which the Granth is written is a script called Gurmukhi (literally "From the Guru's mouth"), which is considered a modern development of the ancient language called Sanskrit.
The Adi Granth was completed in 1604, and installed at the Golden Temple; Baba Buddha ji was appointed as the first Head Granthi. Guru Arjun told his Sikhs that the Adi Granth was the embodiment of the Guru, and should be treated in the same fashion as they respect him. When Guru Arjun first completed the Adi Granth, he placed it upon his own bed and slept on the floor. Its words were written without any spaces or breaks, which nowadays is hard for most people to follow.
Guru Gobind Singh, the tenth and last of the Sikh Gurus to take human form, dictated the entire Granth Sahib at Talwandi Sabo now called Damdama Sahib. Dhir Mal, the son of Baba Gurditta and grandson of Guru Hargobind, had taken possession of the Adi Granth; he refused to give it to Guru Gobind Singh when the Guru asked for it. History has it that Dhir Mal taunted the Guru, "If you are a Guru, then prepare your own."
Guru Gobind Singh recreates holy Granth
Guru Gobind Singh proceeded to dictate it to Bhai Mani Singh, who recorded it on paper. While some have questioned the authenticity of this story, it is well for us to remember that, of course, Guru Gobind Singh was no ordinary person at all. And, in the old days of bards and story-tellers, it was not unusual for them to recite from memory entire epic poems. Hajis, for example can recite the entire Qur'an and many Hindus priests could recite the Mahabarata. In a time when many people could not read or write, oral traditions were very important. The Sri Guru Granth Sahib is composed in raags and set in the form of music and rhythm making it easier to remember.
Guru Gobind Singh included the Shabads of his father, Guru Teg Bahadur, but he did not include his own Shabads; instead, he placed them in a separate Granth, the Dasam Granth. The Dasam Granth is not revered as Guru, however. The great task of re-writing the entire Guru Granth was finally completed in 1705. The "Damdama Sahib Bir" as it is now called was then taken to Nanded where it was installed.
Installation as Perpetual Sikh Guru
Guru Gobind Singh installed this expanded version of the Adi Granth as Guru on October 20, 1708. This day is celebrated today as Guru Gadi Divas (Enthronement Day). At the time of his death, he declared that the Word of God embodied in the Siri Guru Granth Sahib was to be Guru for all time. He said, "O Beloved Khalsa, let any who desire to behold me, behold the Guru Granth. Obey the Granth Sahib, for it is the visible body of the Guru. Let any who desire to meet me, diligently search its Bani." Thus the Word of God, which has manifested as Guru in Nanak, and had passed through the ten incarnations of Guru, was now returned to its form as the Word, the Bani, the Shabad.