Sources have often talked about in terms of publishing format as a way to determine quality; books, scholarly journal article, newspaper, website, magazine, video, etc. Despite the intent to be unbiased, most scholarly, peer-reviewed publications are not perfect. The people who make publishing decisions are mainly white, cis-gender straight people without disabilities. This means that even works focused on diverse populations are not often written by those who identify as part of the diverse group on which they write. Furthermore, the systems developed to organize information and algorithms used to search for information assume that being straight, white, and male is the default.
Changes in the publishing industry and technology have made these formats more accessible to both experts and amateurs alike. This allows for more avenues to publish for those who were previously excluded from scholarly discourse. Open Access Scholarly Journals, self-published materials, and various platforms (ex. YouTube, Medium, Twitter, or individual websites) that allow for a wide range of contributions from both experts and those wanting to spread misinformation.
Because of this, it is vital to think about sources in terms of their originality, how they meet your needs and to have a plan for evaluating your sources.