Unity Script Reference:
Legacy Documentation: Version 4.3.0
Layout
Description

Specifies how banner should be layed out on screen.

Please note that Traditional Banner and Rect Banner (introduced in ios6) use different enum values. If you use "wrong" enum value for current ad type: for Traditional Banner Top* and Center* will be considered Top, and Bottom* will be considered Bottom* for Rect Banner Top will be considered TopLeft and Bottom - BottomLeft.
Variables
Top Traditional Banner: align to screen top.
Bottom Traditional Banner: align to screen bottom.
TopLeft Rect Banner: place in top-left corner.
TopRight Rect Banner: place in top-right corner.
TopCenter Rect Banner: align to screen top, placing at the center.
BottomLeft Rect Banner: place in bottom-left corner.
BottomRight Rect Banner: place in bottom-right corner.
BottomCenter Rect Banner: align to screen bottom, placing at the center.
CenterLeft Rect Banner: align to screen left, placing at the center.
CenterRight Rect Banner: align to screen right, placing at the center.
Center Rect Banner: place exactly at screen center.
Manual Completely manual positioning.