How to use this symbol — in English language
Recently I saw this symbol — used in a weird way. I don’t remember sentence word by word but it was something like this:
Our product can improve your skin — from separate sells, to overall texture.
What are the rules for this symbol????

Question

Answer

Do you mean the em dash (--)?

If so it's used to identify a completely separate section of a sentence that adds some additional information. It's "almost" a replacement for brackets()

Ex:
I understand your question - about punctuation - and hope that I can help.

The section between the em dashes is not required for the sentence to make sense. It adds a bit of extra information, but it could be removed and not change the meaning.

Here's an article about the this and the many other ways it can be used:
https://www.dictionary.com/e/em-dash/

Answer

Do you mean a "dash"? If yes, it is used to emphasize additional information, join independent clauses, mark non-essential information, offset lists placed in a sentence.

Answer

Hi Blake, good question. This symbol, (?) Is a called a question mark. You use it when you are asking a question and you write it at the end of that question.

For example, "What is your name?"

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