ciao, in Italian we use "prenotare" or "riservare", but the word "riservazione" doesn't exist!

For learning Italian, you use "riservazione" (verb "riservare"), or "prenotazione" (verb "prenotare"). Update: Whoops! Then that means the Italians were very kind to me, despite my mistakes, when I was there. ;)

Both the words are synonyms ( same meanings). There is no difference between them, however, in modern times, "reserved" is commonly used instead of "book".