More about dictionaries Crack , the most popular password guessing program, makes extensive use of word collections. Each word is permuted in various ways, encrypted and compared to the target cyphertext. The more words that Crack has available, the more passwords it will guess. The primary function of npasswd is to frustrate bad guys running Crack. To this end, some of Crack has been incorporated into npasswd .
Dictionaries are a set of hash files optimized for fast lookup.
They are constructed from word lists , which are text files with one word per line. The dictionary hash files are created with makedict , which produces files with the suffixes .pwd , .pwi and .hwm . The hash files are probably are not portable between CPU architectures, and take up more disk space their source data. Multiple dictionary directories can be given. The files should be world-readable .