# Time-series visualizations

A time series is a sequence of data points, measured typically at successive points in time spaced at uniform time intervals. Examples of time series are the daily closing value of the Dow Jones index and the annual flow volume of the Nile River at Aswan. Time series are very frequently plotted via line charts. http://en.wikipedia.org/wiki/Time_series

## Sparkline charts

A sparkline is a very small line chart, typically drawn without axes or coordinates. It presents the general shape of the variation (typically over time) in some measurement, such as temperature or stock market price, in a simple and highly condensed way. http://en.wikipedia.org/wiki/Sparkline

## Line/area/scatter/bar charts

A chart is a graphical representation of data, in which "the data is represented by symbols, such as bars in a bar chart, lines in a line chart, or slices in a pie chart".

• A line chart or line graph is a type of chart which displays information as a series of data points connected by straight line segments. http://en.wikipedia.org/wiki/Line_chart
• A bar chart or bar graph is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. A vertical bar chart is sometimes called a column bar chart. http://en.wikipedia.org/wiki/Bar_chart

## Horizon charts

Horizon charts reduce vertical space without losing resolution. Larger values are overplotted in successively darker colors, while negative values are offset to descend from the top. As you increase the number of colors, you reduce the required vertical space. By combining position and color, horizon charts improve perception: position is highly effective at discriminating small changes, while color differentiates large changes.