Thank you for your interest in becoming a new page reviewer. Reviewing new pages is one of the most important maintenance tasks on the whole site. It's what keeps bad pages out and, equally important, it gives a boost to new, good faith users creating their first genuine articles. Before continuing, know that reviewing new pages needs a thorough knowledge not only of deletion and notability guidelines, but also a good understanding of reliable sources. Once you've read this tutorial, please consider applying for the permission.
New page review is a vital function as the front line of interaction between new authors and community members devoted to policing the quality of the project. It has a variety of detailed, quite complex possible actions for patrolling pages in all namespaces. Only new page reviewers can mark pages as 'Reviewed', which releases them for indexing by search engines. Any reviewing action done through the page curation toolbar by a reviewer marks an article as reviewed (adding maintenance tags, nominating for deletion, etc.). If you don't want the article marked as reviewed, you can unreview it by opening the review panel and clicking "Mark as unreviewed".
It is important to review correctly and seriously. Because of the high volume of articles created, even a few percentage points more of erroneous or bitey reviewing can each day adversely affect hundreds of articles and deter many new users from staying on and becoming regular editors. It is critical that editors review with care and diligence. This is not a contest and there is no deadline. New page patrol values quality over quantity.
At its core, new page reviewing is about deciding whether a new article will be marked as approved and accepting it onto Wikipedia, or initiating one of several deletion procedures. Uncontroversial deletions can be proposed using PROD, while most other deletion proposals are resolved in a discussion at Articles for deletion. In a very narrow set of cases, an expedited WP:CSD or WP:BLPPROD can be placed to delete material which is unambiguously not an improvement to Wikipedia. When subpar articles are about subjects that are related to other existing articles on Wikipedia, merging content or simply redirecting the page to the existing article may be preferable to deletion, in which case editors should follow BRD and escalate the discussion to AfD if contested. Draftifying is sometimes used for articles that may have been created by an editor with an undeclared conflict of interest, or to preserve material that may be useful in another article but is not a viable article in its current form. If an article is accepted, new page reviewers may choose to apply maintenance tags for significant problems.
If you have a question or concern, post a message at the New Page Reviewer Talk, and an experienced reviewer or editor will be along soon to help you. For other help using the tools, see the related tabs above.