Ishvara is a philosophical concept in Hinduism, meaning controller or the Supreme controller (i.e. God) in a monotheistic or the Supreme Being or as an "Ishta-deva" of monistic thought. Ishvara is a transcendent and immanent entity best described in the last chapter of the Shukla Yajur Veda Samhita, known as the Ishavasya Upanishad. It states ""ishavasyam idam sarvam"" which means whatever there is in this world is covered and filled with Ishvara. Ishvara not only creates the world, but then also enters into everything there is. In Saivite traditions, the term is used as part of the compound ""Maheshvara"" ("great lord") later as a name for Siva.