For assignments, projects and dissertations you will need to do a literature search: find existing literature and information about your chosen topic to use as evidence in support of arguments or points you make.
You may also be asked to produce a 'literature review'. The aim of a literature review is to show you have identified, summarised and critically evaluated the key research on a particular topic or question. In a literature review, the literature itself is the main subject of discussion and analysis. In order to find the most relevant information in the most efficient way possible, you need to develop an effective search strategy.