The Italian alphabet has 21 letters: 5 vowels and 16 consonants. Listen to the pronunciation here.
The missing consonants from the English alphabet are: j (i lunga), k (cappa), w (doppia vu), x (ics), and y (ipsilon). They only appear in words with foreign origin as in x-ray.
Some differences in pronunciation of consonants are:
H is not pronounced.
C before e or i sounds like CHE or CHI ( like the ch in church in English ).
CH is pronounced like the letter K.
SC is pronounced like SH.
G before e and i is pronounced like J.
S if in between two vowels sound like the English letter Z.
Some useful internet or website conventions:
. punto , dot
/ barra, forward slash
– trattino, hyphen