Docs: Initial bar chart docs (#35155)

* Docs: Initial bar chart docs

* minor tweak

* Another minor tweak

* Updated what's new

* Updated list formatting

* Update bar-chart.md

* Update bar-chart.md

* Review feedback updates

Co-authored-by: Diana Payton <52059945+oddlittlebird@users.noreply.github.com>

docs/sources/panels/visualizations/bar-chart.md

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+title = "Bar chart"
+description = "Bar chart visualization"
+keywords = ["grafana", "docs", "bar chart", "panel", "barchart"]
+weight = 170
++++
+
+# Bar chart
+
+This panel visualization allows you to graph categorical data.
+
+{{< figure src="/static/img/docs/bar-chart-panel/bar-chart-example-v8-0.png" max-width="1025px" caption="Bar chart example" >}}
+
+## Supported data formats
+
+Only one data frame is supported and it needs to have at least one string field that will be used as the category for an X or Y axis and one or more numerical fields.
+
+Example:
+
+| Browser | Market share |
+| ------- | ------------ |
+| Chrome  | 50           |
+| IE      | 17.5         |
+
+If you have more than one numerical field the panel will show grouped bars.
+
+### Visualizing time series or multiple result sets
+
+If you have multiple time series or tables you first need to join them using a join or reduce transform. For example if you 
+have multiple time series and you want to compare their last and max value add the **Reduce** transform and specify  **Max** and **Last** as options under **Calculations**.
+
+{{< figure src="/static/img/docs/bar-chart-panel/bar-chart-time-series-v8-0.png" max-width="1025px" caption="Bar chart time series example" >}}
+
+## Bar chart options
+
+Use these options to refine your visualization.
+
+### Orientation
+
+- **Auto** - Grafana decides the bar orientation based on what the panel dimensions.
+- **Horizontal** - Will make the X axis the category axis.
+- **Vertical** - Will make the Y axis the category axis.
+
+### Show values
+
+This controls whether values are shown on top or to the left of bars.
+
+- **Auto** Values will be shown if there is space
+- **Always** Always show values.
+- **Never** Never show values.  
+
+### Group width
+
+Controls the width of groups. 1 = max with, 0 = min width.
+
+### Bar width
+
+Controls the width of bars. 1 = Max width, 0 = Min width.
+
+### Line width
+
+Controls line width of the bars.
+
+### Fill opacity
+
+Controls the fill opacity bars.
+
+### Gradient mode
+
+Set the mode of the gradient fill. Fill gradient is based on the line color. To change the color, use the standard [color scheme]({{< relref "../standard-options.md#color-scheme" >}}) field option.
+
+Gradient appearance is influenced by the **Fill opacity** setting.
+
+#### None
+
+No gradient fill. This is the default setting.
+
+#### Opacity
+
+Transparency of the gradient is calculated based on the values on the y-axis. Opacity of the fill is increasing with the values on the Y-axis.
+
+#### Hue
+
+Gradient color is generated based on the hue of the line color.
+
+{{< docs/shared "visualizations/tooltip-mode.md" >}}
+
+{{< docs/shared "visualizations/legend-mode.md" >}}
+
+### Legend calculations
+
+Choose which of the [standard calculations]({{< relref "../calculations-list.md">}}) to show in the legend. You can have more than one.
+
+## Text size
+
+Enter a **Value** to change the size of the text on your bar chart.
+
+## Axis
+
+Use the following field settings to refine how your axes display.
+
+Some field options will not affect the visualization until you click outside of the field option box you are editing or press Enter.
+
+### Placement
+
+Select the placement of the Y-axis.
+
+#### Auto
+
+Grafana automatically assigns Y-axis to the series. When there are two or more series with different units, then Grafana assigns the left axis to the first unit and right to the following units.
+
+#### Left
+
+Display all Y-axes on the left side.
+
+#### Right
+
+Display all Y-axes on the right side.
+
+#### Hidden
+
+Hide the Y-axes.
+
+### Label
+
+Set a Y-axis text label.
+
+If you have more than one Y-axis, then you can give assign different labels with an override.
+
+### Width
+
+Set a fixed width of the axis. By default, Grafana dynamically calculates the width of an axis.
+
+By setting the width of the axis, data whose axes types are different can share the same display proportions. This makes it easier to compare more than one graph’s worth of data because the axes are not shifted or stretched within visual proximity of each other.
+
+### Soft min and soft max
+
+Set a **Soft min** or **soft max** option for better control of Y-axis limits. By default, Grafana sets the range for the Y-axis automatically based on the dataset.
+
+**Soft min** and **soft max** settings can prevent blips from turning into mountains when the data is mostly flat, and hard min or max derived from standard min and max field options can prevent intermittent spikes from flattening useful detail by clipping the spikes past a defined point.
+
+You can set standard min/max options to define hard limits of the Y-axis. For more information, refer to [Standard field options]({{< relref "../standard-options.md#max" >}}).

docs/sources/whatsnew/whats-new-in-v8-0.md

@@ -49,7 +49,13 @@ The Prometheus metrics browser allows you to quickly find metrics and select rel
 
 ### Bar chart visualization (beta)
 
-The Bar chart panel is a new visualization that allows categorical data display.
+The Bar chart panel is a new visualization that supports categorical data. It only supports one data frame and it needs to have at least one string field that will be used as the category for an X or Y axis and one or more numerical fields.
+
+{{< figure src="/static/img/docs/bar-chart-panel/bar-chart-example-v8-0.png" max-width="1025px" caption="Bar chart example" >}}
+
+To use it with time series you first have to add a **Reduce** transform.
+
+For more information, refer to [Bar chart visualization]({{< relref "../panels/visualizations/bar-chart.md" >}}).
 
 ### State timeline visualization (beta)