Diphthong and Silent Letter

Hye guys!!!Today I learn something new.Today I learned about DIPHTHONG.Do you know what is Diphthong?

=a sound formed by the combination of two vowels in a single syllable, in which the sound begins as one vowel and moves towards another (as in coin, loud, and side ).

This video explain more about it 

While SILENT LETTER meaning is a letter that, in a particular word, does not correspond to any sound in the word's pronunciation  .Phonetic transcriptions  that better depict pronunciation and which note changes due to grammar and proximity of other words require a symbol to show that the letter is mute.