What is "Synthesizing Info"?
The Merriam-Webster dictionary defines synthesis as: "the composition or combination of parts or elements so as to form a whole"; "the combining of often diverse conceptions into a coherent whole"
When you synthesize while writing a paper, you are combining the separate thoughts and ideas of the authors of your sources with your own thoughts and ideas. This is what makes a well-written, balanced research paper. A paper that is nothing but your own thoughts and ideas, unsupported by any other sources, is an opinion paper - not a research paper.
On the other hand, a paper that is just citations, with no thoughts, ideas, or new perspectives of your own is just a summary of your sources. This type of paper, in which you organize and summarize individual sources, is common in high school (book reports, etc.). In college-level research you will be expected to start synthesizing resources with your own thoughts, balancing your views with the views of others to create new perspectives on your research topics and become part of the conversation!
This video by the librarians at UNLV provides a nice introduction.