Learn Italian: È un segreto tra me e te. - It is a secret between you and me.

After prepositions like tra (between), Italian uses tonic (or stressed) pronouns instead of regular subject pronouns. That is why we use me instead of io, and te instead of tu.

Why is there no word for 'It' before È?

In Italian, you do not need to use a pronoun when the subject is 'it'. The verb È already means 'it is' (as well as 'he is' or 'she is') all by itself.

Can tra mean anything else besides 'between'?

Yes, it can also mean 'among' when talking about a larger group. Because it is connecting two specific people here, 'between' is the right translation. You will also often see the word fra, which means the exact same thing as tra.

Is it rude to put myself first by saying me e te instead of te e me?

Not at all! In English, we are taught to put the other person first and say 'you and me' to be polite, but in Italian, me e te (me and you) is the standard, natural way to say it and is not considered rude.