There are many different Hebrew names for God, but the most common are "Yahweh," "Elohim" and "Adonai." Each has a slightly different meaning, but all are used to refer to God.
Out of the many Hebrew names for God, the most common is Yahweh. It means "Lord" or "Jehovah," and it is used 6,519 times in the Old Testament. It is the name of God revealed by none other than God Himself in Exodus 3, considered by the Jews to be too holy to say out loud. For this reason, it is often spelled without vowels as "YHWH." Because of this, it is no longer known whether the name is properly pronounced "Yahweh" or "Jehovah," so both pronunciations are common.
Another Hebrew name for God is "Elohim," which is used over 2,000 times in the Old Testament. It simply means "God." A final name for God is "Adonai," meaning "Lord" or "Master," and it is used 434 times in the Old Testament. This name is often used as a substitute for "Yahweh." The Jews' preoccupation with the name of God may come from the third of 10 commandments given by God to Moses and the people of Israel in Exodus 20 which says "Thou shalt not take the name of the LORD thy God in vain" (Exodus 20:7).