For your class research, you will often need to use a variety of these sources. You may already know about Primary sources versus Secondary sources from previous classwork.
Primary sources are information sources that provide first-hand accounts or evidence about an event, object, person, or work, such as diaries, letters, speeches, memoirs, photographs, interviews, news articles, journal articles etc.
Secondary sources are information sources that describe, interpret, explain, analyze, and/or evaluate primary sources, such as textbooks, biographies, news articles, journal articles, etc.
You’ll notice that some of those Primary and Secondary source examples overlap. A news article can, for example, describe a research study which would make it a Secondary source. The next news article from the same paper can provide a first-hand account of an event making that article a Primary source. You’ll need to look at the content of the source to know whether it is a Primary or Secondary source.