MetaCharacters

MetaCharacters is an option to StringPosition. With MetaCharacters -> None, no strings have special meanings. MetaCharacters -> {c1, c2, c3} specifies the metacharacters for pattern escape, single character matching and multiple character matching. MetaCharacters -> Automatic is equivalent to MetaCharacters -> {"\\", ".", "*"}.

Please visit the official Wolfram Language Reference for more details and examples on core symbols.