A theme is an idea of significance that is presented repeatedly and/or prominently in an artistic work, and it is often related to the joys and struggles that one experiences through life. It can usually be identified by the amount of important literary devices (e.g. plot, setting, metaphor, dialogue, etc.) that contribute to emphasizing it.
When identifying a theme for an assignment, however, you must be careful not to state it in too vague a manner. For example, though "love," "war," or "jealousy" can be significant ideas in an artwork, they are too broad to be written about successfully in an essay. Therefore, to narrow your topic, try asking the journalistic questions of "who," "what," "where," "when," "why," and "how": for example, whose love? love for whom? what type of love? love in what time or place? why or how did the love begin or end? Such questions will lead you to more specific themes that can work for essays, such as "the pain of love that is unreturned," "the trauma that war inflicts on people," or "middle-class jealousy of a neighbor's success."
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