YHVH - HaShem - "The Name"
"These four letters are usually transliterated from Hebrew as YHVH in Latin, YHVH in German, French and Dutch, and YHWH in English. This was variously rendered as "Yahweh" or "Jehovah", since in Latin there was no distinct lettering to distinguish 'Y' from 'J', or 'W' from 'V', and the Hebrew does not clearly indicate the omitted vowels. In English translations, it is often rendered in small capital letters as "the LORD", following Jewish tradition which reads the word as "Adonai" ("Lord") out of respect for the name of God and the commandment not to take the name of God in vain.
The word "haŠem" 'the Name' is also used in Jewish contexts; in Samaritan, "Šemå" is the normal substitution." (wikipedia) Hebrew teaching tells us that the actual name of G-d is hidden from man. Moses and the high priest knew the actual name. Because Hebrew is made up of consonants the vowels were known by the reader and from tradition until later times when the vowels were added by a system of additional marks and dots below the letters. This would be like taking my name KEITH and taking out the E and the I and spelling it KTH. Only those who know me would know my real name.
Why was this done? Hebrew teaching would say that it is to honor and respect G-d. I can relate to that. I taught high school for 28 years and I began that the first year letting the students call me Keith. One year was enough. The lack of respect for me was enormous. Hebrew sages teach that the name is not to be uttered and thus use HaShem which means "the name" to address G-d. They teach that HaShem is so holy and different from us that treating Him with familiarity by calling Him by His first name can lead to contempt.
Yeshua continued to use LORD and began His prayer with "Our Father who art in heaven" using the familiar term of Aba for the Father. That was not meant to show disrespect any more than calling my dad daddy is contempt. Calling my dad "Jim" would be the equivalent disrespect of calling G-d by His full name. So to the Gentile believer it is important to see G-d as Holy while understanding that just as the letter Aleph implies the strong arm of G-d comforting and protecting his baby or child our Father in heaven does likewise.