The content area consists of a section, a row and a column. Section is a root type container that allows to group multiple rows. Section can contain only rows and it can’t be inserted into any other element.
Row is a main part of the content area. It allows to build composite layouts by inserting inner rows and dividing a page into logic blocks with columns.
Columns are part of the row which carry your content elements inside them. You can click and drag columns between rows.