PR to document Explore Metrics (previously datatrails) (#85212)

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Co-authored-by: lwandz13 <larissa.wandzura@grafana.com>

docs/sources/explore/explore-metrics.md

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+---
+labels:
+  products:
+    - cloud
+    - enterprise
+    - oss
+title: Explore Metrics
+aliases:
+description: This topic describes the Explore Metrics feature
+weight: 200
+---
+
+# Grafana Explore Metrics
+
+Grafana Explore Metrics is a query-less experience for browsing **Prometheus-compatible** metrics. Quickly find related metrics with just a few simple clicks, without needing to write PromQL queries to retrieve metrics.
+
+{{% admonition type="warning" %}}
+Explore Metrics is currently in [private preview](/docs/release-life-cycle/). Grafana Labs offers support on a best-effort basis, and breaking changes might occur prior to the feature being made generally available.
+{{% /admonition %}}
+
+With Explore Metrics, you can:
+
+- easily slice and dice metrics based on their labels, so you can immediately see anomalies and identify issues
+- see the right visualization for your metric based on its type (gauge vs. counter, for example) without building it yourself
+- surface other metrics relevant to the current metric
+- “explore in a drawer” - expand a drawer over a dashboard with more content so you don’t lose your place
+- view a history of user steps when navigating through metrics and their filters
+- easily pivot to other related telemetry, including logs or traces
+
+You can access Explore Metrics either as a standalone experience or as part of Grafana dashboards.
+
+## Standalone experience
+
+To access Explore Metrics as a standalone experience:
+
+1. Click the arrow next to **Explore** in the Grafana left-side menu and click **Metrics**. You are taken to an overview page that shows recent metrics, bookmarks, and the option to select a new metric exploration.
+1. To get started with a new exploration, click **+ New metric exploration**.
+1. Select **Prometheus** or any Prometheus-compatible data source available in the drop-down menu under **Data source**.
+1. Click **+ Add label** to select a label-value pair from the drop-down menu. You can add multiple label-value pairs. A label type will appear above the selected label with a drop-down list of options from which to choose. For example, if you select the label `container` a drop-down list of available containers appears.
+1. You can also search for metrics using keywords under **Search metrics** in the search bar.
+1. Use the time picker to select a date and time range from the drop-down menu or use an absolute time range.
+1. Click the down arrow next to the **Refresh** icon to set a refresh rate from the drop-down menu. The default is `Off`.
+1. Click the **Settings** icon and toggle **Always keep selected metric graph in-view** to keep your main graph always in view on the Breakdown drill-down tab.
+
+The **History** button in the upper left corner tracks every step navigating through metric exploration.
+
+![show metrics explore overview](/media/metrics-explore/metrics-explore-overview.png)
+
+### Metrics exploration
+
+To further explore a metric, click **Select** in the upper right corner of the metric visualization.
+
+![show select box](/media/metrics-explore/select-metric.png)
+
+- The **Overview** tab provides a description for each metric, as well as the metric `type` and `unit` associated with the metric. It also provides a list of labels associated with the metric. Click on any label to view drill-down visualizations.
+- The **Breakdown** tab depicts time series visualizations for each of the label-value pairs for the selected metric. You can further drill down on each label and click **Add to filter** to add the label/value pair into your filters. You can also change the **View** from grid to rows.
+- The **Related metrics** tab depicts related metrics with relevant key words. You can repeat the drill down process for any related metric. Toggle **SHow previews** to preview visualizations.
+
+Once you have gathered your metrics exploration data you can:
+
+- Click the **Explore** icon on the right side to open the graph in Explore, where you can modify the query or add the graph to a dashboard or incident.
+- Click the **Share** icon on the right side to copy the metric drill down URL to the clipboard so it can be shared.
+- Click the **Star** icon on the right side to bookmark and save the metrics exploration.
+
+## Dashboard experience
+
+To access Explore Metrics via a dashboard:
+
+1. Navigate to your dashboard.
+1. Select a time series panel.
+1. Click the panel menu in the upper right and select **Explore Metrics**. If there are multiple metrics, click on the one you want to explore.
+1. You will see a slide out drawer with the Metrics Experience, starting with the drill down. You can access the standalone experience by clicking **Open** in the upper right.