In most Bible translations, the word “LORD” in all capital letters is the Hebrew word typically rendered “Jehovah”. Directly transliterated it is “YHVH” without vowels. A few Bibles do translate YHVH as “Jehovah” rather than “LORD”, but this is not typical.
Jehovah is the biblical name of the Almighty God. It means “the Self-existent One,” “He who becometh,” or “the becoming one.” (God does not need anything outside of Himself to live or exist.) This name belongs exclusively to our Creator, our Heavenly Father. It is never applied to any other being.
The word “God” is not a proper name but means “a mighty one”. It is the Hebrew word “elohim”. While this word is often used alongside Jehovah’s name (LORD God), it is not used exclusively in this manner. It is also used to describe other “mighty ones” in the Bible. We see an example of this in Deuteronomy 5:7, where in the first commandment, Jehovah told Israel that they were to have no other gods (elohim) before Him. Anything or anyone that we make “mighty” or elevate to a position in our lives that rightfully belongs to Jehovah can become a god or idol (false god). Jehovah warned Israel against this idolatry to protect them from going astray and from losing His favor.
1 Corinthians 8:5-6 tells us “for even if there are so-called gods whether in heaven or on earth, as indeed there are many gods and many lords, yet for us there is one God, the Father from whom are all things and we for Him; and one Lord, Jesus Christ, by whom are all things, and we through him.” For the Christian, then, we see only Jehovah as the Almighty God, our Heavenly Father. His son, Jesus, is God’s principal agent of creation (by whom are all things). Jesus is our Lord or master.
For a discussion about God’s name, “I AM THAT I AM”, please see the FAQ – “Why did God call Himself, “I AM THAT I AM”?”