Standard Italian is the official language of the country and it is based on the old Tuscan Florentine dialect.
However, as you can probably imagine, Standard Italian also differs from the modern Florentine dialect as it changed throughout the years.
Standard Italian is primarily used in formal settings, education, media or literature, and it acts as a lingua franca, allowing Italians from different regions to communicate effectively.
What might surprise you is that a very small percentage - around 1% of the population - can speak a totally neutral and pure Italian, as their regional accent and dialect might influence the way they speak.