Accents, language, dialects and alphabets.
The history of Italy has played its part. Do you know how many letters are in the Italian alphabet?
Current Italian alphabet (l'alfabeto) contains 21 letters.
(16 consonants and 5 vowels. Vowels can also have diacritics.)
There are also 5 foreign letters that are found in foreign words.
The letters J, K, W, X and Y are not part of the proper alphabet.
If you are interested in also knowing the names of the letters:
Learning the Italian Alphabet
This is indeed not covered by the Duolingo course.
It's nice that you often bring up interesting topics.
It is commonly said that Italian (as a language) has seven vowels, not five, as the dual pronunciation of 'e' and 'o' (open and close) phonetically count as separate sounds.
At the beginning of the 20th century, in times when the linguistic unification of the country was still a long way to come, some linguists had suggested to spell the e's and o's using different glyphs, according to their sound, but the proposal was dismissed.
In the case of a doubtful pronunciation, a graphic accent (either acute or grave) can be optionally placed on the relevant vowel, e.g. pésca vs. pèsca, but this happens rather seldom.
It's a shame that the proposal was dismissed. I like Italian but that has always been my main gripe with the language.
Even French with its terrible orthography can usually distinguish é, è, e in writing.
A different spelling may have been an aid for learners, but it would have been a useless complication for native speakers.
The doubt about Italian vowels may concern only the e's and o's that carry the word's stress, because unstressed ones take only the close sound.
Moreover, in different parts of the country many words are commonly spoken with the wrong e's and o's as a consequence of the local dialect inflection, and are perfectly understood all the same.
A perfect diction is a desirable goal, but it is no longer considered an essential requirement, not even for TV anchormen (as it used to, decades ago). Maybe would-be theatre actors are the only ones left who still attend diction courses.
The problem is that in Italy we have Italian and then we also have many dialects ..dialects are languages that derive from Italian but are not 100% Italian...some southern Italian dialects are similar to the Romanian language for example...the ''sardo'' dialect (from sardinia) it is officially considered a language other than Italian...
The history of Italy is quite interesting. At one point, it was strongly Spanish so unsurprisingly both Italian and Spanish are close. I understand that Standard Italian is not really used in a family setting.