In the scientific literature, review articles are 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 'secondary' scientific journal, with examples including Annual Reviews, the Nature Reviews series of journals and Trends. A peer review is the process by which scientists assess the work of their colleagues that has been submitted for publication in the scientific literature. A software review is also a form of peer review, by the co-workers.

A consumer review refers to a review written by the owner of a product or the user of a service who has sufficient experience to comment on reliability and whether or not the product or service delivers on its promises, otherwise known as product reviews.. An expert review usually refers to a review written by someone who has tested several peer products or services to identify which offers the best value for money or the best set of features. A bought review is the system where the creator (usually a company) of a new product pays a reviewer to review his new product.

Book review
A book review (or book report) is a form of literary criticism in which a book is analyzed based on content, style, and merit. It is often carried out in periodicals, as school work, or online. Its length may vary from a single paragraph to a substantial essay. Such a review often contains evaluations of the book on the basis of personal taste. Reviewers, in literary periodicals, often use the occasion of a book review for a display of learning or to promulgate their own ideas on the topic of a fiction or non-fiction work. At the other end of the spectrum, some book reviews resemble simple plot summaries.

Music reviews

Performance reviews
Reviews of live music performances are typically short articles that tell readers about the performers or group(s) that were involved and the pieces or songs that were performed. The comments made by reviewers fall, roughly into two categories: technical comments and subjective/artistic comments. The elements in the "technical" category include rhythmic "togetherness", intonation, errors or slip-ups, and so on. These elements are fairly "black and white"; a pianist playing a concerto either played the right notes on a climactic scale run, or she missed it. The subjective comments refer to elements which are a matter of taste. The balance between the different elements in a review (information about the performer or group; information about the pieces/songs; commentary about the technical and subjective elements of the performance) depends on the audience that a music critic is writing for. Music reviewers writing in local newspapers or general-interest magazines may not be able to assume that the readers will be familiar with music performers and pieces/songs, so they may decide to include a great deal of "background" information.

Recording reviews
Music critics and music writers also review recordings of music, including individual songs or pieces or entire albums. In the case of a review of an entire album, the reviewer will not only judge the individual songs or pieces; they will also judge how well all of the songs or pieces work together or go together. The age of digital downloads may considerably change the album review. Where previously albums were purchased as collections of songs, often with a common theme, the rise of individual song downloads may have significant impact on consumers' exposure to an artist's music. Die-hard fans will most likely continue to explore an artist's complete work; but individuals will most likely make significantly different choices and "cherry-pick" songs they have been exposed to. The concept of "singles" or individual hits marked for retail has been around for long time; however the price for a single in the days of CDs or 45's was much closer to the complete album price. When you consider that each song on an artist's album is often priced at the same amount, the odds of the average consumer purchase the entire album instead of selecting the "hit" songs decreases significantly.

Composition reviews
In Classical music, music critics may also do reviews of compositions, even if the piece or song has never been performed and it only exists on manuscript paper in a score. To review a composition in this fashion, the critic will use music theory skills such as harmonic analysis and thematic analysis, along with their knowledge of idioms and compositional practices.

Bought review
A bought review is the system where the creator (usually a company) of a new product pays a reviewer to review his new product. Primarily used in the car, movie and game industry this system creates a kind of undercover advertising. Bought reviews tend to be biased due to the financial relationship the reviewer has with the makers of the product or item that is being evaluated—although exceptions occur. Nielsen (2009) proposes a framework for scholarly or academic reviews of dictionaries, but this framework may also be extended to other types of reviews. In particular, the requirement that reviews must provide useful information to the intended audience and the requirements to the informative value of reviews. In some cases, a bought review may be independent, if the person that is hired to do the review has a strong reputation for independence and integrity. Even if a "bought review" from a respected critic is actually independent, the perception of potential bias will remain, due to the financial relationship between the company and the critic.

A similar type of review that may be biased is the so-called "puff piece", a review of a product, film, or event that is written by a sympathetic reviewer or by an individual who has a connection to the product or event in question, either in terms of an employment relationship or other links. For example, a major media conglomerate that owns both print media and record companies may instruct one of its employees in one of its newspapers to do a review of an album which is being released by the conglomerate's record company. Although some journalists may assert their professional independence and integrity, and insist on producing an unbiased review, in other cases, writers may succumb to the pressure and pen a biased "puff piece" which praises the product or event while omitting any discussion of any shortcomings. In some cases, "puff pieces" purport to provide a review of the product or event, but instead merely provide "peacock words" ("An amazing recording"); "weasel words" ("probably one of the most important albums of the 2000s") and tabloid-style filler which is peripheral or irrelevant to assessing the qualities of the product or event ("During the filming, there were rumours that romantic sparks flew between the two co-leads, who were often seen talking together on the set").