When performing research in books at the LRC or in LRC-subscribed databases, you can be reasonably confident that you are using good sources. But when visiting other websites, it's not always so clear whether the information is appropriate for your research. When in doubt, use the CRAAP test, and consider the following aspects of the information:
Currency: the timeliness of the information
Relevance: the importance of the information for your needs
Authority: the source of the information
Accuracy: the reliability, truthfulness, and correctness of the content
Purpose: the reason the information exists
To read more about the questions you should be asking, see the original CRAAP test from California State University, Chico.