In German, "w" is pronounced "v". Appartently the spelling YHWH comes from German schollarship and so the correct transliteration into English is YHVH though it is often still written as YHWH. Basically it is the Hebrew letters "yod", "he", "vav" (again the name of this letter is often written as "waw") and another "he" and it is from this that we get Yahveh which was probably how it was pronounced. Yahveh is the personal name of the God of the Old Testament, whom the Jews claimed as their God.
54 Jesus answered, "(91) If I glorify Myself, My glory is nothing; (92) it is My Father who glorifies Me, of whom you say, 'He is our God'; - John 8:54 NASB
The Son says that if He glorifies Himself, His glory is nothing, it is His Father who glorifies Him. If the Father were the Son and the Son the Father, Jesus would be glorifying Himself which He Himself said would be nothing. As God, the Son is refered to in the Old Testament as YHVH, just as His Father is (YHVH in most cases refers to the Father whom as already mentioned, the Jews claimed as their God). The person of God who was speaking through the Prophet Isaiah was the Holy Spirit.
The Father is head and thus preminent in the Godhead. He is the voice from heaven who declared that Jesus was His Son. He is YHVH of hosts who sent YHVH of hosts after glory.
3 But I want you to understand that Christ is the (5) head of every man, and (6) the man is the head of a woman, and God is the (7) head of Christ. - 1 Corinthians 11:3 NASB
The Son reveals the Father. He is YHVH of hosts who has been sent after glory by YHVH of hosts.
22 "(1) All things have been handed over to Me by My Father, and (2) no one knows who the Son is except the Father, and who the Father is except the Son, and anyone to whom the Son wills to reveal Him." - Luke 10:22
The Holy Spirit is the Helper whom YHVH of hosts has sent from YHVH of hosts. He convicts the world of sin and righteousness and guides into all truth. It is He who spoke through the Prophets, He is the Spirit of YHVH and Himself YHVH.
7 "But I tell you the truth, it is to your advantage that I go away; for if I do not go away, the (12) Helper will not come to you; but if I go, (13) I will send Him to you.
8 "And He, when He comes, will convict the world concerning sin and righteousness and judgment;
9 concerning sin, (14) because they do not believe in Me;
10 and concerning (15) righteousness, because (16) I go to the Father and you no longer see Me;
11 (17) and concerning judgment, because the ruler of this world has been judged.
12 "I have many more things to say to you, but you cannot bear them now.
13 "But when He, (18) the Spirit of truth, comes, He will (19) guide you into all the truth; for He will not speak on His own initiative, but whatever He hears, He will speak; and He will disclose to you what is to come.
14 "He will (20) glorify Me, for He will take of Mine and will disclose it to you.
15 "(21) All things that the Father has are Mine; therefore I said that He takes of Mine and will disclose it to you. - John 16:7-15 NASB
36 "David himself said in the Holy Spirit,
'(29) THE LORD SAID TO MY LORD,
"SIT AT MY RIGHT HAND,
UNTIL I PUT YOUR ENEMIES BENEATH YOUR FEET."' - Mark 12:36 NASB
16 "Brethren, (34) the Scripture had to be fulfilled, which the Holy Spirit foretold by the mouth of David concerning Judas, (35) who became a guide to those who arrested Jesus. - Acts 1:16 NASB
25 who (33) by the Holy Spirit, through the mouth of our father David Your servant, said,
'(34) WHY DID THE [1] GENTILES RAGE,
AND THE PEOPLES DEVISE FUTILE THINGS? - Acts 4:25 NASB
2
"(3) The Spirit of the LORD spoke by me,
And His word was on my tongue. - 2 Samuel 23:2 NASB
13 Then Samuel took the horn of oil and (19) anointed him in the midst of his brothers; and (20) the Spirit of the LORD came mightily upon David from that day forward. And Samuel arose and went to Ramah. - 1 Samuel 16:13 NASB
3 But Peter said, "Ananias, why has (3) Satan filled your heart to lie (4) to the Holy Spirit and to (5) keep back some of the price of the land?
4 "While it remained unsold, did it not remain your own? And after it was sold, was it not under your control? Why is it that you have conceived this deed in your heart? You have not lied to men but (6) to God." - Acts 5:3-4 NASB