The timeline in which information is published impacts what you find. For example, the day of an event you can find messages on Twitter, but you won't find a comprehensive study. A year after an event you may be able to find the first longer, more scholarly sources on the topic. This list is ordered from most immediate to least, which coincides with least researchd/contextualized to most. To some extent, this also moves from primary to secondary to teritary resources as well.
Wikipedia and Google provide a huge amount of information, but it's information that hasn't been vetted. Anyone can contribute to Wikipedia and Google automatically indexes millions of web pages.
That being said, Wikipedia and Google can be helpful tools for getting started in your research. Both can help you identify keywords or synonyms that might be helpful in your search. Wikipedia often includes bibliographies that include refereed articles. You can use this as a starting reading list that leads to other useful sources.
Before you begin to use the Internet for your research, answer the following questions.
There are a number of guides to help you determine the validity and usefulness of information. Here's one of our favorites:
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