  Incrementality is ubiquitous in human-human interaction and beneficial for
human-computer interaction. It has been a topic of research in different parts
of the NLP community, mostly with focus on the specific topic at hand even
though incremental systems have to deal with similar challenges regardless of
domain. In this survey, I consolidate and categorize the approaches,
identifying similarities and differences in the computation and data, and show
trade-offs that have to be considered. A focus lies on evaluating incremental
systems because the standard metrics often fail to capture the incremental
properties of a system and coming up with a suitable evaluation scheme is
non-trivial.
