Most fiction and nearly all poetry is currently published only by literary magazines. In addition, many of these magazines publish creative nonfiction of various sorts. Frequency of publication ranges from weekly (such as The New Yorker), to monthly, to quarterly (four times a year) or less. Some of these publications accept material only from experienced writers, from agents or by solicitation (meaning they contact writers themselves); many others are open to beginning writers. All expect a certain level of professionalism in submissions.
Remember that most literary magazines receive upwards of 300 manuscripts a month, from which even the largest will only be able to select a few. Take the inevitable rejections in stride: it is not at all uncommon to hear of writers who submitted a work ten times, twenty times, or more, only to be finally have their work be accepted for publication or even win a prize. So much depends on individual taste. Persistence pays off!
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