Editing Estimated time of arrival (section)

==Overview==
One of the more common uses of the phrase is in [[public transportation]] where the movements of [[train]]s, [[bus]]es, [[airplane]]s and the like can be used to generate estimated times of arrival depending on either a static timetable or through measurements on [[traffic]] intensity.{{citation needed|date=July 2012}} In this respect, the phrase or its abbreviation is often paired with its complement, '''estimated time of departure'''<!--boldface per WP:R#PLA--> ('''ETD'''), to indicate the expected start time of a particular journey. This information is often conveyed to a [[passenger information system]] as part of the core functionality of [[intelligent transportation system]]s.

For example, a certain flight may have a calculated ETA based on the [[speed]] by which it has covered the [[distance]] traveled so far. The remaining distance is divided by the speed previously measured to roughly estimate the arrival time.{{citation needed|date=July 2012}} This particular method does not take into account any unexpected events (such as new wind directions) which may occur on the way to the flight's destination.{{citation needed|date=November 2014}}

ETA is also used [[metaphor|metaphorically]] in situations where nothing actually moves physically, as in describing the time estimated for a certain task to complete (e.g. work undertaken by an individual; a computation undertaken by a [[computer program]]; or a process undertaken by an organization). The associated term is "estimated time of accomplishment", which may be a [[backronym]].{{citation needed|date=July 2012}}