Reviewers and readers expect to find certain information at specific locations within the manuscript. Reviewers will tell you to move incorrectly positioned items, such as a result placed in the Methods. The reader who does not find your topic statement at the end of a discussion or introduction section is not about to search the remainder of the manuscript, they will probably move on to another paper. Knowing what to write in each section makes your job much easier. Plus, you can expect more readers if the Title is attractive and the abstract is informative.
The following pages describe the sections of a typical scientific manuscript. Case reports are considered in an additional series of pages.
Information is interpreted more easily and more uniformly if it is placed where most readers expect to find it.