- filter
$filter=are use to filter out latters that is not in the word - contain
$contain=are use to collect all latters the are in the word but in wromg placement. - perfect
$perfect=are use to collect all latters that are in correct position with the word. The input format is$perfect=000where 0 is replace with space.$perfect=000erin this example, all the word will end with -er.