Italian has diphthongs when you put together two vowels, like in the word "uomo". As far as I understand a diphthong is not necessarily a glide, because a glide has to be less sonorous than a vowel. So I'm asking: are there real glides in Italian, and can you provide examples?
It really depends on how the language treats those kinds of vowel-vowel pairs. If the 'uo' in 'uomo' is treated like a single vowel, then it's a diphthong; but if the 'u' is treated like a consonant, then it's a glide.
Basically, a diphthong is when a vowel-vowel sequence is treated like one vowel; and a glide is when one vowel in a vowel-vowel sequence is treated instead as a consonant. (Really, it's not that glides have lower sonority than vowels, it's that vowels have their relative sonority level reduced when they're used as glides.)