Not only that!
If you ask an Orthodox Jew, "How are you doing?" instead of responding directly, the response will generally be, "Barukh Hashem." This means, "Blessed is the Name [of the Lord.]" It is a way of saying, "Fine," by instead declaring the blessedness of the reason he is fine.
If you make an appointment with such a person, and ask if he can make it, instead of saying, "Yes," he will say, "Eem yirtza Hashem," meaning, "The [Lord's] Name willing" [I'll be there.] If there is a chance he may have to change the appointment he may add, "B'lee neder," meaning, "Not a vow." This is to honor the biblical commandment that vows must be kept.
bob>I think gentiles don't understand our word is a vow. "Let your yes be yes and your no be no" I found out long ago when asked to do something not to just say "yes" but "If I can I will" or "looks like I can" people count on our word/vow and when we don't carry it out we cause them trouble. They also may not think much of us/me either from then on.
Num. 30:3 If a man makes a vow to the Lord, or swears an oath to make a prohibition on himself, he shall not violate his word; according to whatever came out of his mouth.
We routinely substitute, "Hashem," meaning, "The [Lord's] Name" to avoid saying in vain the four letter unpronounceable Hebrew Name of God, called "the Tetragrammaton." Some will even write "G-d" or "Gd," to avoid writing the generic term. But many scholars consider this prohibition only applicable in the Hebrew language.
bob>When is His actual four letter name used?
Other than in prayer we purposely avoid saying even the generic Hebrew Term by mispronouncing it. We say, "Elokaynoo" with a "k" instead of an "h."