Technical or research reports also produce the results of research or scientific inquiry, and often are published by educational or governmental agencies, or research institutes. They are harder to find, and may not be peer-reviewed, but do proved quick access to research. They are similar to conference papers. World Wide Web sites can be the most difficult to evaluate. Informational Web sites often end in .edu or .gov , relating to educational or governmental sources.
Sites ending in .org , organizations, can also be useful.
Their main purpose might be advertising. Currency is a most important criterion for a Web site. Primary sources usually present an idea or hypothesis, a research methodology, data or arguments to support the hypothesis, and conclusions about the results. If the source is not describing the results of empirical research, then it must present original material, or a new interpretation of previously published ideas. Secondary sources gather together primary information to review or evaluate it, or to present an overview of the subject.