Az angolok a W-t miért "dupla u"-nak mondják?

When Old English was written, it used a mixture of Latin letters and older runes. One of these runes was Wynn, which was used to represent the wound that w gives today:

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That runes was sometimes replaced by the combination uu - a double u - for the same sound.

In german, the letter v changed in sound to be pronounced as f in most cases (it still is). In a few cases the v-sound was retained. To distinguish these cases, scribes began to write vv for these.

When printing was developed in what is today Germany (and to some extent Italy, but that is less relevant here), the printing press manufacturers made types for the letters that they had. Since the combination vv was very common, they made a letter for it - w. In most languages letter is called "double-v".

These printing presses and the letters for them were exported everywhere, including to England. The English quickly realized that they didn't have types for all their letters, so they made do with what they had. Since English didn't have the w before printing, they simply reused that letter for the Wynn rune, which was missing. It is called "double-u" because it was also sometimes written as "uu"

Similar story for the letter Thorn, which was also missing when printing and became the "th" combination.

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