X-bar Schema
The X-bar schema combines left- and right-branching. The standard X-bar schema has the following structure:
This structure is both left- and right branching. It is left-branching insofar as the bar-level projection of the head (X') follows the specifier, but it is right-branching insofar as the actual head (X0) precedes the complement. Despite these conflicting traits, most standard X-bar structures (in English) are more right-branching than left-branching because specifiers tend to be less complex (i.e. fewer words) than complements.
Read more about this topic: Branching (linguistics)