The Line of Time : Backgrounds and Usage of Event-Timelines

One of the most prevalent parameters in visualized data is time. A large part of information visualization concerns time-series data, where a progress or shift is shown over time. In this survey paper we want to look at the special case of event timelines that aim for giving an overview over a sequence of events that all belong to a superior topic. Timelines can for example show happenings in the news, the biography of a person or the history of a company, the development of a certain technology or a review of events that led to or influenced a historic event. In most cases events are aligned along a horizontal line, which represents the progression in time from left to right. It seems like a commonly accepted representation, but how much insight do we really get through timelines and how do people read and understand them? Moreover there are some issues arising during the design process of a timeline, e.g. when the dates are distributed irregularly, when there are long periods of time where we don’t know the density of events or when a date is not defined precisely. We will look at those challenges and how several different tools and techniques try to solve them, especially in the domains of science and journalism even though time constraints and a general technophobia showed up to be reasons for not using them too often.