A review is an evaluation of a publication, such as a movie, video game, musical composition, or book or a piece of hardware like a car, appliance, or computer. In addition to a critical statement, the review's author may assign the work a rating (for instance, one to five stars) to indicate its relative merit. More loosely, an author may review current events or items in the news.
In terms of scientific literature, reviews is a category of scientific paper, which provides a synthesis of research on a topic at that moment in time. A compilation of these reviews forms the core content of a 'tertiary' scientific journal, with examples including Annual Reviews, the Nature Reviews series of journals and Trends.