Some indications

• * : represents any number of unknown characters (except space)
• + : represents a positive number of unknown characters (save space)
• . : represents a single unknown character (except space)
• .' : represents an unknown alphanumeric character, followed by an apostrophe
• [] : define a list of authorized characters
• - : indicates a search interval (to put between square brackets) or a dash
• ^ : indicates a character to ban (to put between square brackets)
• () : delimit a choice between character sequences
• | : indicates a choice between two sequences (to put between brackets)
• ? : indicates the presence or not of the preceded character
• $ : indicates the end of the searched expression