Add additional info for time series

source/core/timeseries-collections.txt

@@ -19,10 +19,31 @@ Time Series Collections
 .. versionadded:: 5.0
 
 :term:`Time series collections <time series collection>` efficiently
-store sequences of measurements over a period of time. Compared to
-normal collections, storing time series data in time series collections
-improves query efficiency and reduces the disk usage for time series
-data and :term:`secondary indexes <secondary index>`.
+store sequences of measurements over a period of time. Time series data
+is any data that is collected over time and is uniquely identified by
+one or more unchanging parameters. The unchanging parameters that
+identify your time series data is generally your data source's metadata.
+
+.. list-table::
+   :header-rows: 1
+   :widths: 30, 30, 40
+
+   * - **Example**
+     - **Measurement**
+     - **Metadata**
+   * - Weather data
+     - Temperature
+     - Sensor identifier, location
+   * - Stock data
+     - Stock price
+     - Stock ticker, exchange
+   * - Website visitors
+     - View count
+     - URL
+
+Compared to normal collections, storing time series data in time series
+collections improves query efficiency and reduces the disk usage for
+time series data and :term:`secondary indexes <secondary index>`.
 
 Procedures
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