According to scientists (linguists and psycholinguists), about a thousand words are enough for the average person "with his head" for everyday life. Nevertheless, the vocabulary of the educated European is about ten to twenty thousand. We are talking about active use, while we can know and understand about two to two and a half times more words.
But as soon as a person plunges into any specialty, branch of knowledge, a topic - at least knitting or sawing - he also needs means of expression specific to this sphere. And if we are constantly dealing with documents - we just definitely need the most diverse types of dictionaries. Linguists and translators have a habit of using such reference literature - after all, this is their specialty. The most popular types of dictionaries among them are, first of all, bilingual and multilingual - which translate words into one or several languages. There are monolingual, and thesauruses, and
dictionaries of any specific group. For example, foreign words, etymological (explaining the origin of the token), explanatory. All types of dictionaries of the Russian language are even difficult to list. If you need to find out what a particular word or concept means, you should use an explanatory dictionary (for example, edited by Ozhegov or Dahl) or an encyclopedic dictionary.
However, not all words can be included in such publications: for example, they may not contain highly specialized terminology. In this case, these types of dictionaries are needed, in which special (medical, technical, mathematical) terms are collected. And the meaning of the idiom - well, at least "put aside" or "eat a dog" - we will check according to the dictionary of phraseological units. Especially often, such reference books are needed by translators of fiction and simply studying a foreign language. After all, if in your own phraseological unit it is clear from the context, then it will not be possible to translate it verbatim into English or German, retaining the meaning.
There are also so-called “reverse” types of dictionaries - if usually the words are arranged in alphabetical order by the first, second and subsequent letters, then, for example, the rhyme dictionary represents the endings of words and sorting goes in the opposite direction.
If we mention dictionaries of the Russian language, the types of which are very diverse, it is necessary to say about frequency and semantic dictionaries.
In such directories, words are grouped by frequency of use or by thematic groups: from the core (the most important tokens in this topic) to the periphery.
There are also types of dictionaries such as spelling - they can be used to check the spelling of a word, orthoepic - with which sound and pronunciation are checked, dialectic (or regional), where vocabulary of a certain territorial group is collected and explained (so-called dialects). Neologisms, obsolete words - that is, those that have either recently entered the language and have not yet been sufficiently mastered by them, or have not been used for a long time - are presented in the corresponding dictionaries (historicisms, obsolete words, new words). Finally, such types of dictionaries are created that represent the work of a particular writer or poet, with comments explaining the specifics of their use of certain words. These include, for example, "Dictionary of the language of A.S. Pushkin", "Dictionary of the works of Yesenin" and others.