Yahweh is another name for God. It’s a form of the Hebrew name used for God. God is known by many names. Yahweh is thought to be another transliteration of Jehovah, the name that God revealed to Moses in Exodus 3:14. The Jews regarded the name as too sacred to be spoken, and it’s vowel sounds are uncertain. In Hebrew, it’s only YHWH.
See this resource for more history on the origins of the name: Yahweh Translation, Meaning & Facts.
Exodus 3:14 – And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.
It’s important to note that in English translations of the Bible (like in the verse above) that LORD spelled in all caps is a translation for Yahweh (YHWH).
To learn more about the origins of the name Yahweh, see the following link: Blue Letter Bible: Why is God Called Yahweh?