1. The letters F, V, U, Y, W

2. Were all ultimately derived from the sixth letter of the semitic alphabet: ‘vav’

3. Y and F: From Semitic to Greek
The semitic ‘vav’ became two letters in Greek:
the upsilon Y (pronounced /u/)
the digamma F (pronounced /w/)
(no V, U or W)

4. F: From Greek to Latin
The Greek digamma became the Latin F, pronounced /f/, and this continued into modern Latin alphabets.
This leaves us with Y, U, V, W to sort out.

5. Y and V: From Greek to Latin
The Greek Y-shaped upsilon developed into two classical Latin letters: the Y and the V.
V was pronounced either /u/ or /w/
“Arma virvmqve canō”
Y was pronounced /j/, used mainly for Greek-derived words (physica)

6. Y: From Latin to modern English
Y – came straight into English as /j/ (in initial position) and /i/ in final position or medial.
In Middle English, ‘y’ was often used in medial position, instead of ‘i’ (e.g. ‘kyng’, ‘fyr’). Later replaced in most words by ‘i’. Today ‘y’ is relatively rare in medial position, mostly initial or final.
Later the rounded form y was introduced to make it easier to join it with the following letter.

7. W: Middle English to Modern English
In Middle English the /w/ sound was represented by the ‘wynn’ symbol ‘ƿ’, but scribes started using a digram ‘uu’ (double-u) because of the confusion with the letter ‘p’.
It is actually written ‘double v’ because of the initial identification of ‘u’ and ‘v’ as one letter.
By the 13th century it had taken over completely as representing /w/, and the wynn symbol had disappeared.

8. U and V: From Latin to modern English
V – in Middle English this divided into a rounded U and angular V, both used for either /v/ or /ʌ/ /ʊ/ (the difference was only in spelling, whether the letter came at the beginning or middle of a word, was combined with a vowel or consonant).
Only in the 18th century did writers begin to differentiate consistently between consonantal v and the vowel u.
chart

9. Alphabet