Numerous studies have dealt with the coding of information sources within and across languages. These studies have shown that despite the significant differences in the number of formally distinct evidentiality categories, languages tend to have grammaticalized markers for certain information sources, but not for others; different kinds of sensory perception, inference, assumption and hearsay evidence are among those information sources that receive explicit coding. In this paper, another evidence type, namely general knowledge, will be examined. It will be shown that general knowledge differs from other information sources in its nature, but it also has features in common with them. In addition, a formal-functional typology of general knowledge coding will be proposed based on the nature of the element used for this purpose. Finally, the rationale behind the discussed types and the central theoretical implications of the paper will be discussed. The attested types either stress the peculiar nature of general knowledge providing evidence for its independent information source status, or they emphasize the common features shared by general knowledge and other information sources, most notably reliability of information.