Peer review is the evaluation of work by one or more people of similar competence to the producers of the work.

It constitutes a form of self-regulation by qualified members of a profession within the relevant field.

Peer review methods are employed to maintain standards of quality, improve performance, and provide credibility.

In academia, scholarly peer review is often used to determine an academic paper's .

Peer review can be categorized by the type of activity and by the field or profession in which the activity occurs, e.g., .

Open access (OA) refers to online research outputs that are free of all restrictions on access (e.g. access tolls) and free of many restrictions on use (e.g. certain copyright and license restrictions).

Open access can be applied to all forms of published research output, including peer-reviewed and non peer-reviewed academic journal articles, conference papers, theses, book chapters, and monographs.

Open access (OA) journals are scholarly journals that are available online to the reader "without financial, legal, or technical barriers other than those inseparable from gaining access to the internet itself." They remove price barriers (e.g. subscription, licensing fees, pay-per-view fees) and most permission barriers (e.g. copyright and licensing restrictions).

While open access journals are freely available to the reader, there are still costs associated with the publication and production of such journals.

Some are subsidized, and some require payment on behalf of the author.

Research comprises "creative work undertaken on a systematic basis in order to increase the stock of knowledge, including knowledge of humans, culture and society, and the use of this stock of knowledge to devise new applications." It is used to establish or confirm facts, reaffirm the results of previous work, solve new or existing problems, support theorems, or develop new theories.

A research project may also be an expansion on past work in the field.

Research projects can be used to develop further knowledge on a topic, or in the example of a school research project, they can be used to further a student's research prowess to prepare them for future jobs or reports.

To test the validity of instruments, procedures, or experiments, research may replicate elements of prior projects or the project as a whole.

The primary purposes of basic research (as opposed to applied research) are documentation, discovery, interpretation, or the research and development (R&D) of methods and systems for the advancement of human knowledge.

Approaches to research depend on epistemologies, which vary considerably both within and between humanities and sciences.

There are several forms of research: scientific, humanities, artistic, economic, social, business, marketing, practitioner research, life, technological,etc.

For a broader class of literature, see Academic literature.

Scientific literature comprises scholarly publications that report original empirical and theoretical work in the natural and social sciences, and within an academic field, often abbreviated as the literature.

Academic publishing is the process of contributing the results of one's research into the literature, which often requires a peer-review process.

Original scientific research published for the first time in scientific journals is called the primary literature.

Patents and technical reports, for minor research results and engineering and design work (including computer software), can also be considered primary literature.

Secondary sources include review articles (which summarize the findings of published studies to highlight advances and new lines of research) and books (for large projects or broad arguments, including compilations of articles).

Tertiary sources might include encyclopedias and similar works intended for broad public consumption.