What is the sixth letter?

We can prove for an absolute fact that ו is a w. First that sounds is right at home with Semitic languages but are often thought to be peculiar to European languages. So what is our proof? Two Hebrew letters are used to represent long vowels quite often. One is yod and the other is? You guessed it, WAW! There is a reason why yod is used, it is what we call a glide or consonantal vowel. A glide is a consonant that you cannot pronounce at the end of a syllable. You can do this with a v. The only other glide that exists in Hebrew is w. It is logical for the two glides to be used to represent vowels.