Understanding Content Layout
This may sound a little confusing to you between Layouts and Content Layouts but the concept is pretty easy and straight forward. Following figure shows the difference between Layout and Content Layout:
In the above figure, all the light grey colored area is part of Layout (or we can call it Master Layout) and the yellow colored area is what we call Content Area.
Now, the Content Layout is set in this area with having its own four sections:
Following figure tells the position of these four section in the content area: