Popular sources are written for an audience that the website is attempting to attract for marketing purposes. In other words, the website publisher is trying to make money by attracting lots of page views.
There are many different levels of popular sources, in terms of website integrity. That is why the CRAAP test, or any other type of evaluation, is so important to use for these websites.
You should keep in mind that many news websites do not want to endanger their brand by acting irresponsibly and unreliably. Still, many others have lower scruples regarding their integrity. The bottom line: The more you read and apply the CRAAP test, the better you'll get at determining website reliability.
Examples of popular sources: CNN, NY Times, Washington Post, Fox News, Rolling Stone, the Atlantic, Mercury News, SF Chronicle.
Scholarly sources are written by academics and other experts and contribute to knowledge in a particular field by sharing new research findings, theories, analyses, insights, news, or summaries of current knowledge.
Scholarly sources can be either primary or secondary sources. They can also come in many different formats. Books, articles, and websites can all be scholarly sources.
"What Counts As a Scholarly Source?" University of Toronto Libraries |, 18 May 2018, onesearch.library.utoronto.ca/faq/what-counts-scholarly-source.