Sikhism is based on the spiritual teachings of Guru Nanak, the first Guru (1469–1539), and the nine Sikh gurus that succeeded him. The Tenth Guru, Guru Gobind Singh, named the Sikh scripture Guru Granth Sahib as his successor, terminating the line of human Gurus and making the scripture the eternal, religious spiritual guide for Sikhs. The Guru Granth Sahib is notable for actually being written by the founders of the religion, and for including works by members of other religions. Sikhism rejects claims that any particular religious tradition has a monopoly on Absolute Truth.
The Sikh scripture opens with Ik Onkar (ੴ), its Mul Mantar and fundamental prayer about One Supreme Being (God). Sikhism emphasizes simran (meditation on the words of the Guru Granth Sahib), that can be expressed musically through kirtan or internally through Nam Japo (repeat God's name) as a means to feel God's presence. It teaches followers to transform the "Five Thieves" (lust, rage, greed, attachment, and ego). Hand in hand, secular life is considered to be intertwined with the spiritual life.Guru Nanak taught that living an "active, creative, and practical life" of "truthfulness, fidelity, self-control and purity" is above the metaphysical truth, and that the ideal man is one who "establishes union with God, knows His Will, and carries out that Will".Guru Hargobind, the sixth Sikh Guru, established the political/temporal (Miri) and spiritual (Piri) realms to be mutually coexistent.
The majority of Sikh scriptures were originally written in the Gurmukhī alphabet, a script standardised by Guru Angad out of Laṇḍā scripts used in North India. Adherents of Sikhism are known as Sikhs, which means students or disciples of the Guru. The anglicised word 'Sikhism' is derived from the Punjabi verb Sikhi, with roots in Sikhana (to learn), and Sikhi connotes the "temporal path of learning".