Headlines define the structure of an outline tree. The headlines in Org start with one or more stars, on the left margin1. For example:
* Top level headline ** Second level *** 3rd level some text *** 3rd level more text * Another top level headline
Some people find the many stars too noisy and would prefer an outline that has whitespace followed by a single star as headline starters. Clean view, describes a setup to realize this.
org-special-ctrl-a/e to configure special behavior
of C-a and C-e in headlines.