Abstract: Data E of index words C and their description D are stored in a large capacity memory medium (ROM). The data E is read by means of a ROM player, an index word C once retrieved and all or a portion of its description are stored in a RAM memory in the form of a word lists characterized by an attribute note to define the nature of the list, such as memorized and unmemorized words. A learing assistant function is provided to recall selected words from the list, permitting a user to practice the user's memory etc. The dictionary may be in a single language in which the words indexed and their descriptions are indicated by the single language, e.g. the English-English dictionary etc., or the dictionary may be in multiple or plural languages in which the index word C and its description D are indicated by different languages, e.g., the English-Japanese dictionary etc.