Anyone can publish on the web. There is no quality control such as that provided by librarians who select items for their collections. This gives you the opportunity to do the quality control yourself, which can be empowering. But it makes it important for you to develop skills in evaluating information.
To evaluate online information, consider the following criteria:
How credible or believable is the source? Consider:
Credentials: academic background, institutional affiliation, or previously published work.
Arguments: Are arguments for the author's point of view logical and well reasoned?
Documentation: Are facts and arguments supported by references to existing scholarly literature by reputable authors, organizations, or sources?
A source may have excellent credentials and yet be of limited value. In some cases, a source with less impressive credentials may turn out to be highly valuable.
Does the source seem to have a hidden agenda or rigidly narrow point of view?
Does the source distort other points of view or dismiss them out of hand?
Does the source accept advertising? If so, does the advertising appear to bias the information?
Is there a conflict of interest? Does the source stand to profit financially or politically from a particular point of view?
Although financial motivations can cause information to be biased, keep in mind that many corporate sites are excellent sources of free, valuable information. Just remember to look at the information in context.
Does the author give supporting documentation for facts presented?
Is the cited documentation reputable?
Are significant generalizations supported by facts?
Does the information contradict other reliable sources?
Does the text include numerous typos? This can be an indicator of an overall lack of accuracy or poor proof-reading.
You may choose to overlook a minor discrepancy or factual error in an otherwise valuable source. But if you notice such a mistake, it makes sense to be somewhat skeptical. There may be other errors or omissions that you don't notice but that undermine the quality of the information.
Is the information current?
Currency may be extremely important for topics that are changing on a daily basis, such as information about Internet software and technologies. For other topics, such as a historical survey, currency may be less of an issue.
The web page should state the name of its author (or institution) and the date it was last modified or reviewed. Of course, the fact that a page was recently modified or reviewed doesn't guarantee that the information it contains is up to date. Check the dates of cited information and search for more recent versions.
Is the information relevant to your topic?
During your initial search, explore broadly so that you won't exclude anything that you may later decide is important.
As you refine your search, your topic will probably become narrower and fewer items will be relevant.
Is the information relevant to your topic?
When you identify your key sources, you will have more stringent requirements and even fewer items will be relevant.
Does the home page have a site map or menu to give you a sense of the overall structure of the site?
Does the organization of the site make sense to you?
Do you have to move through many screens to find the information you want?
Is the text divided into coherent chunks with headings that are easy to scan?
Is the text well written and concise?
Do graphics and visual cues reinforce the content, or are they a distraction?
Do pages with graphics take a long time to download?
A web site that is easy to use is more fun and inviting. This encourages us to explore and to learn. A site that is very difficult to use may not be worth your trouble. Bad design does not equal bad information, but your "skepticism meter" should turn on.
Some sites are designed for interactive learning while others serve primarily as a means of distributing documents. In the second case, you could decide to print out pages of the site rather than reading online.