This is the 1st most frequent Italian word.
di
"Di" in Italian means "of" or "about" in English.
Here, "di" is used to indicate the material or content of something, meaning "containing" or "made of" in English.
Un bicchiere di vino, per favore.
A glass of wine, please.
In this case, "di" introduces the topic of conversation, similar to "about" in English.
Parliamo di musica.
Let's talk about music.
Here, "di" is used to denote possession, comparable to the English possessive "of".