Peer review is a well-accepted indicator of quality scholarship. It is the process by which an author's peers read a paper submitted for publication. A number of recognized researchers in the field will evaluate a manuscript and recommend its publication, revision or rejection. Articles accepted for publication through a peer-review process implicitly meet the discipline's expected standards of expertise.
There are three different forms of peer review:
Single blind review: The reviewers know who the author is, but the reviewers are anonymous.
Advantages:
The author cannot influence the reviewer.
Disadvantages:
Reviewers doing research in the same area can stop a publication in favour of their own publication.
Reviewers can hide behind the cloak of anonymity, and therefore be unnecessarily harsh or critical, or give a low-quality review.
Double blind review: the author and the reviewers are anonymous.
Advantages:
The reviewer does not prejudge based on the author's reputation.
The reviewer gives good evaluations based on quality and not on the basis of favouritism or familiarity.
Disadvantage:
Double blind review is not so blind in certain 'niche' disciplines. An author can often still be recognized from the style or topic.
Open review: the author and reviewers are known to each other.
Advantage:
There is less chance of plagiarism, misuse, poor quality comments, and acting out of self-interest by the reviewer.
Disadvantage:
There is more chance that reviewers allow themselves to be influenced by favouritism, abuse of power and fear of expressing a critical opinion on the work of an authority in the field.
The process usually starts with the editor who will decide whether the article fits the journal's scope and focus and whether the author has adhered to the journal's stylistic specifications.
The editor will then send the article to a number of reviewers (or referees). The reviewers are scholars in the relevant field and peers to the author(s) of the article. Usually, there are two or three referees for a given article. Each of the reviewers read the article and return an assessment to the editor, indicating problems and suggestions for improvement.
Based on the reviewers' recommendations the editor will decide :
Source: http://www.elsevier.com/reviewers/peer-review/peer-review-diagram