How can grep not contain rows starting with a certain character?

How can grep not contain the regular expression of a row starting with a certain character: ^: the starting flag of the row? For example, ^ ben indicates matching the row starting with ben. $: Indicates the end of a row. For example, "ben $" indicates that the row ended with "ben" is matched. [^]: Match any character except [^ character. For example, 9 [^ 0] does not match 90, but matches. How to Use the [html] [user @ sever] $ grep '^ [^ #]' files command to select a line not starting with # As the output