Improve your English by avoiding common pronunciation errors. Learn why overgeneralising rules for silent letters and sounds like 's' can be a mistake.
The answer partly depends on whether we are talking about the sounds or letters of vowels and consonants. By mentioning “alphabetic languages”, the questioner is presumably asking why most versions of ...
Consonants are the rest of the letters in the alphabet: b, c, d, f, g, h, j, k, l, m, n, p, q, r, s, t, v, w, x, y and z The letter 'y' is a bit different, because ...