Who is leading the chase? – The dynamics of research fields
As a researcher, every time you enter a new research field or start to work on a new problem you need to review the knowledge that is out there already and find out about what is currently being done in that field. A great part of getting to know what is actually out there is usually done with some sort of literature review or survey. Sometimes, a literature review is a formal part of the first year of grad school and is completed in the form of a write-up.