# Glossary ### Animation An option for including motion when a chart is first drawn or redrawn after modification. Read more at [Animation](https://developers.google.com/chart/interactive/docs/animation). ### Annotations Static labels for data points in a chart. [`annotation`](https://developers.google.com/chart/interactive/docs/roles#annotationrole) is a column role available to [`DataTable`](https://developers.google.com/chart/glossary#datatable) and [`DataView`](https://developers.google.com/chart/glossary#dataview) classes, not to be confused with [Annotation Charts](https://developers.google.com/chart/interactive/docs/gallery/annotationchart). ### Axis A reference line in a chart indicating the measurement of coordinates. In Google Charts, the two main axes are categorized as either: - horizontal vs. vertical - domain vs. target Google Charts does not call them "x" and "y" axes because this would be ambiguous: Google Charts allows the user to break the traditional association between the "axis showing domain values" and the "horizontal axis," and it would not be clear which one "x axis" describes. For example, you can flip the orientation of a chart to show the domain variables on the vertical axis. ### Callback A piece of executable code that is passed as an argument to a second piece of code, which is expected to "call back," or execute, the first piece of code at a later time. In Google Charts, callbacks are commonly used with [library loaders](https://developers.google.com/chart/glossary#libraryloader) and [event handlers](https://developers.google.com/chart/interactive/docs/events). Example: "Set a callback to run when the Google Charts library is loaded." ### Chart Type A combination of data representation, appearance, and options that is implemented as a JavaScript object. Examples of chart types include [Pie Charts](https://developers.google.com/chart/interactive/docs/gallery/piechart) and [Bubble Charts](https://developers.google.com/chart/interactive/docs/gallery/bubblechart). See the [Charts Gallery](https://developers.google.com/chart/interactive/docs/gallery) for a full list. ### ChartEditor The user interface for editing Google Charts on the fly, which you can include in any web page. Read more at [ChartEditor](https://developers.google.com/chart/interactive/docs/reference#google_visualization_charteditor). ### ChartWrapper A JavaScript class that wraps your chart and can handle all loading, drawing, and [queries against Datasources](https://developers.google.com/chart/interactive/docs/queries#overview) for your chart. ChartWrappers are required when using [Dashboards](https://developers.google.com/chart/glossary#dashboard) and [ChartEditor](https://developers.google.com/chart/glossary#charteditor). Read more at [ChartWrapper](https://developers.google.com/chart/interactive/docs/reference#chartwrapper-class). ### Column Role A property of a column in a [`DataTable`](https://developers.google.com/chart/glossary#datatable) that describes its purpose. For example, the [`tooltip`](https://developers.google.com/chart/interactive/docs/roles#tooltiprole) column role is assigned to columns that store tooltip text. Read more at [What roles are available?](https://developers.google.com/chart/interactive/docs/roles#what-roles-are-available) and [` getColumnRole`](https://developers.google.com/chart/interactive/docs/reference#DataTable_getColumnRole) ### Column Type The data type assigned to a column in a [`DataTable`](https://developers.google.com/chart/glossary#datatable). Column types can be one of the following: - `string` - `number` - `boolean` - `date` - `datetime` - `timeofday` Read more at [` getColumnType`](https://developers.google.com/chart/interactive/docs/reference#DataTable_getColumnType). ### Continuous Having a smooth progression of consecutive values. Used to describe an axis where a variable can take on any value between two given values, as opposed to a [discrete](https://developers.google.com/chart/glossary#discrete) axis. Read more at [Discrete vs Continuous](https://developers.google.com/chart/interactive/docs/customizing_axes#Discrete_vs_Continuous). Example: "The major axis of a chart can be either discrete or continuous." ### Control A user interface widget on a dashboard, such as sliders or autocompleters, which allows the viewer to alter the data or charts that are part of a dashboard. Example: "This dashboard contains a control that lets you select an option from a drop-down menu." Read more at [Controls and Dashboards](https://developers.google.com/chart/interactive/docs/gallery/controls). ### Core Charts The most popular chart types in Google Charts. You can load all core charts simultaneously by using the `corechart` package; read more at [Basic Library Loading](https://developers.google.com/chart/interactive/docs/basic_load_libs#basic-library-loading). The core chart types are: - [Area Charts](https://developers.google.com/chart/interactive/docs/gallery/areachart) - [Bar Charts](https://developers.google.com/chart/interactive/docs/gallery/barchart) - [Bubble Charts](https://developers.google.com/chart/interactive/docs/gallery/bubblechart) - [Candlestick Charts](https://developers.google.com/chart/interactive/docs/gallery/candlestickchart) - [Column Charts](https://developers.google.com/chart/interactive/docs/gallery/columnchart) - [Combo Charts](https://developers.google.com/chart/interactive/docs/gallery/combochart) - [Histogram Charts](https://developers.google.com/chart/interactive/docs/gallery/histogram) - [Line Charts](https://developers.google.com/chart/interactive/docs/gallery/linechart) - [Pie Charts](https://developers.google.com/chart/interactive/docs/gallery/piechart) - [Scatter Charts](https://developers.google.com/chart/interactive/docs/gallery/scatterchart) - [Stepped Area Charts](https://developers.google.com/chart/interactive/docs/gallery/steppedareachart) ### Dashboard A visual display that combines chart and [control](https://developers.google.com/chart/glossary#control) instances, typically with at least one chart and one control. If a dashboard contains multiple charts, they must all have the same data source. Read more at [Controls and Dashboards](https://developers.google.com/chart/interactive/docs/gallery/controls). ### DataTable A JavaScript class that represents a two-dimensional, mutable table of values. Read more at [DataTable Class](https://developers.google.com/chart/interactive/docs/reference#DataTable). ### DataView A JavaScript class that is derived from a [`DataTable`](https://developers.google.com/chart/glossary#datatable). A `DataView` can serve as a data source for Google Charts, but unlike a `DataTable`, it is read-only. A `DataView` auto-updates when the underlying `DataTable` is changed, with some exceptions. Read more at [DataView Class](https://developers.google.com/chart/interactive/docs/reference#dataview-class). ### Discrete Referring to a set of values that are not based a [continuous](https://developers.google.com/chart/glossary#continuous) value system. In the context of Google Charts, "discrete" can describe data types or axes. Read more about discrete axes at [Discrete vs Continuous](https://developers.google.com/chart/interactive/docs/customizing_axes#Discrete_vs_Continuous)." Example: "A list of countries should be stored as a column with a discrete data type." ### Domain The set of all possible inputs which a function or relation can take. If multiple data series are shown in a chart, it is possible for one domain value to have multiple target values. Example: "For the domain value '3', this data series has value '5'." ### Event Pre-defined actions that a Google Chart can register, such as a user clicking a button. The page for each chart type contains an Events section (example [here](https://developers.google.com/chart/interactive/docs/gallery/linechart#events)) listing the events supported by that chart type, such as `ready`, `select` and `onmouseover`. Example: "When the user clicks 'I want apples,' this throws a `userWantsApples` event." Read more at [Handling Events](https://developers.google.com/chart/interactive/docs/events). ### Formatter Determines how the data in a [`DataTable`](https://developers.google.com/chart/glossary#datatable) column is displayed without affecting the underlying values. Google Charts provides a pre-defined list of formatters and formatter options. For example, you can use the `prefix` option of the [NumberFormat](https://developers.google.com/chart/interactive/docs/reference#numberformatter) formatter to display the value "1000" as "$1000." Read more at [Formatters](https://developers.google.com/chart/interactive/docs/reference#formatters). ### Google Sheets Google Sheets allows users to create, update, modify, and share spreadsheets online. Google Sheets are a common data source for Google Charts. Read more at the Google Charts page on [Google Sheets](https://developers.google.com/chart/interactive/docs/spreadsheets). You can create and manage Google Sheets from [Google Drive](https://drive.google.com). ### Interval An optional column role which contains additional target values for given domain values in a data series. For example, you can store data about [confidence intervals](https://en.wikipedia.org/wiki/Confidence_interval) in an `interval` column in order to display it as part of a bar chart. Intervals are most commonly displayed in line, scatter, and bar charts. Google Charts offers several styles for displaying intervals; read more at [Intervals](https://developers.google.com/chart/interactive/docs/gallery/intervals). ### Legend An area within a chart which lists the label and visual appearance of all data series in a chart, and/or the visual sub-components of a single data series in a chart. For example, in a pie chart which contains only one data series, the legend will contain the label and color corresponding to each "slice" of the pie. ### Library Loader The JavaScript method `google.charts.load`, which loads the Google Charts API library. Loading the library is necessary whenever you build a web page that uses Google Charts. Read more at [Load the Libraries](https://developers.google.com/chart/interactive/docs/basic_load_libs). ### Method A procedure in [object-oriented programming](https://en.wikipedia.org/wiki/Object-oriented_programming) (OOP) that is associated with an object class. Example: "If you write a chart library, your `Chart` object must expose a `draw()` method. ### Query A request for information issued against a database. Google Charts supports [Data Queries](https://developers.google.com/chart/interactive/docs/queries), which are SQL-like queries used to query sources such as Google Sheets. Queries must be written using the [Google Visualization API Query Language](https://developers.google.com/chart/interactive/docs/querylanguage). ### Series A data column in a [`DataTable`](https://developers.google.com/chart/glossary#datatable) or [`DataView`](https://developers.google.com/chart/glossary#datatview), where each value corresponds one-to-one with a domain value from the domain column. A series may have one or more associated columns which have different column roles, e.g. annotation or style roles. Example: "The following chart demonstrates a chart with two series, one in dark blue, one in light blue." ![Bar chart showing two series: Cats and Dogs.](https://chart.googleapis.com/chart?cht=bvg&chs=175x75&chd=t:20,30,40%7C25,35,45&chco=4D89F9,C6D9FD&chdl=Cats%7CDogs&chbh=10,1,6&chxt=x,y&chxl=0:%7CJan%7CFeb%7CMar) ### Stacking A chart option for displaying multiple data series where each series is graphed relative to the preceding series by adding up all previous series values for a given domain value. This creates the visual effect of the series being "stacked" on top of each other. For an example, see [Area Chart: Stacking Areas](https://developers.google.com/chart/interactive/docs/gallery/areachart#stacking-areas). Stacking is available for the following chart types by setting the `isStacked` option to `true`: - [Area Charts](https://developers.google.com/chart/interactive/docs/gallery/areachart) - [Bar Charts](https://developers.google.com/chart/interactive/docs/gallery/barchart) - [Column Charts](https://developers.google.com/chart/interactive/docs/gallery/columnchart) - [Stepped Area Charts](https://developers.google.com/chart/interactive/docs/gallery/steppedareachart) ### Style A column role which uses specific properties to determine the appearance of a series. Properties include `color`, `opacity`, `stroke-width`, and `stroke-color`. Read more about the [`style`](https://developers.google.com/chart/interactive/docs/roles#stylerole) column role in [What Roles are Available?](https://developers.google.com/chart/interactive/docs/roles#what-roles-are-available) ### Tooltip The small boxes that pop up when your cursor hovers over certain chart components. Tooltip content can be either automatically generated from the underlying series data or stored in a column with the `tooltip` column role. Read more at [Tooltips](https://developers.google.com/chart/interactive/docs/customizing_tooltip_content). ### Trendline A line superimposed on a chart that reveals the overall direction, or "trend," of the data. Read more at [Trendlines](https://developers.google.com/chart/interactive/docs/gallery/trendlines). [Back to top](https://developers.google.com/chart/glossary#top)