In the Old Testament, we find genres such as law, historical works, prophecy, psalms, and so forth. Whether ‘wisdom literature’ is a genre is disputed: it is supposed to cover Job, Proverbs, and Ecclesiastes. But Job has little in common with the other two books.
Not only whole books, but individual texts within books, may be distinguished according to genre. Thus we have different types of law in the Pentateuch: it is easy to see the difference between the impersonal regulations of (e.g.) Exodus 21:28-32 (so-called ‘casuistic’ law) and the personal appeal of (e.g.) Exodus 22:25-27 (sometimes called ‘apodictic law’). There are different types of psalms (see Psalms), and different genres in Proverbs: chiefly the ‘instruction’, personally addressed, in most of chapters 1-9 and the impersonal ‘wisdom sentences’ in chapters 10-29.
The discipline of ‘form criticism’ seeks to define genres originating in oral communication and determine the social situations in which they were at home.