A ForwardLink is any link directly created on a given hypercontent (er, page) to another hypercontent (er, page). For instance, when I explicitly SmashWordsTogether, I create a ForwardLink to "SmashWordsTogether".
The link doesn't need to be an InlineLink. But it has to have been created with the express intent of being from a page A to a page B. The "forward" direction would be A --> B then.
Contrast BackLink, which is B --> A.
See also BidirectionalLink