In text with niqqud, a dot is added to the left or on top of the letter to indicate, respectively, the two vowel pronunciations.
It is the origin of Greek Ϝ (digamma) and Υ (upsilon), Cyrillic У and V, Latin F and V and later Y, and the derived Latin- or Roman-alphabet letters U and W.
It is often literally translatable to "By..." or "I swear to...", and is often used in the Qur'an in this way, and also in the generally fixed construction والله wallāh ("By Allah!"
[2]: I §356d, II §62 The word also appears, particularly in classical verse, in the construction known as wāw rubba, to introduce a description.
[2]: II §§84-85 With an additional triple dot diacritic above waw, the letter then named ve is used to represent distinctively the consonant /w/ in Arabic-based Uyghur,[3] Kazakh and Kyrgyz.
[3] Also found in Quranic Arabic as in صلۈة ṣalāh "prayer" for an Old Higazi /oː/ merged with /aː/, in modern spelling صلاة.
Consonantal vav (ו) generally represents a voiced labiodental fricative (like the English v) in Ashkenazi, European Sephardi, Persian, Caucasian, Italian and modern Israeli Hebrew, and was originally a labial-velar approximant /w/.
The vowel can be denoted without the vav, as just the dot placed above and to the left of the letter it points, and it is then called ḥolam ḥaser.
Compare the three: Vav can also be used as a mater lectionis for [u], in which case it is known as a shuruk, and in text with niqqud is marked with a dot in the middle (on the left side).
Vav at the beginning of the word has several possible meanings: (Note: Older Hebrew did not have "tense" in a temporal sense, "perfect," and "imperfect" instead denoting aspect of completed or continuing action.
Modern Hebrew verbal tenses have developed closer to their Indo-European counterparts, mostly having a temporal quality rather than denoting aspect.