Why don old telephones have the letters Q or Z on them?
The plan was to have letters for the numbers 2-9. 1 and 0 never had letters associated with them. With eight numbers and three letters per number, you can use 24 of the letters. So, there are two extra. “Q” looks like “O” and “Z” looks like “2” and these two letters are not common in English. So, it was decided to leave these two out to avoid confusion. Note that “I” used even though it looks like “1” because I is a very common letter.
