The Tetragrammaton are the four Hebrew letters for the word God, yud hey vahv hey, that God used to reveal himself to Moses. The name is commonly translated as He brings into existence whatever exists. People do not know how the name was pronounced. When the Temple existed, it was pronounced by the High Priest once during the high during the High Holidays each year. The name was probably once ubiquitous in the Tanak but was largely replaced by the Masoretes between the 6th and 10th C AD