Students often receive research assignments requiring the use of credible sources. But what does it mean for a source to be "credible"? Why is it important to use these sources? And how can you tell if a source is credible? When we describe a source as "credible," we’re basically saying that the information is high quality and trustworthy. Essentially, that we can believe what the source is telling us. When you use high-quality sources to back up your points, you demonstrate your own credibility as a writer, thereby contributing to the overall effectiveness of your argument. The best quality research builds on other high quality research. This is true of both your own work and the work of professional researchers. There are several factors that contribute to a source's credibility. Among them are the author's level of expertise, her point of view, and the source's publication date. The author's level of expertise on the topic he or she is writing about could take the form of an advanced degree or other extensive experience in the field. A credible source often provides information about the author's credentials. Sometimes, however, the author's credentials may not be listed, and the publication itself can be the marker of quality. This is often true for some non-scholarly publications like well-respected newspapers and magazines, where the article's content is critically examined as part of the publication process. Another important component of a source's credibility is its point of view, in particular its potential bias. Bias is an inaccurate or unfair presentation of information. In some cases, bias is intentional. A group with its own agenda may sponsor research or information, and this sponsorship may influence the results. Bias can also be unintentional. A writer's perspective may prevent him or her from being able to see all sides of an issue. Sometimes you need unbiased facts to support your point. But other times you might want people's opinions, and that's OK as long as you acknowledge the source's perspective in your work. While bias can be difficult to detect, be aware that it can exist in any kind of source, including things you find through the library. In the academic publishing world, books and articles go through a rigorous editorial process in which an editor or group of scholars evaluate the work's quality. When it comes to journal articles, this process is called peer review. Peer-reviewed articles are considered high quality, because the review process helps to filter out sources that are written by unqualified or biased authors. Finally, with any source, consider when it was published or last updated. Even something that was once high-quality can now be out-of-date and unsuitable for some purposes. If I needed current statistics on the average cost of college in the United States, a source published in the 1990s would be out of date. However, if I were looking at the the increase in college tuition over the last few decades, a source from the 1990s might fit my purposes. Of course, not every credible source is appropriate for your research. Be sure to evaluate not only a source's trustworthiness, but also its appropriateness for your argument. For help finding credible sources or determining whether a source you've found is credible, ask a librarian!