Update overview.md (#1837)

* Update overview.md

* Update designing-reports/connecting-to-data/data-items/grouping-data/overview.md

Co-authored-by: Copilot <[email protected]>

---------

Co-authored-by: Copilot <[email protected]>

Author: todorarabadzhiev

designing-reports/connecting-to-data/data-items/grouping-data/overview.md

@@ -11,26 +11,28 @@ previous_url: /data-items-grouping-data, /designing-reports/connecting-to-data/d
 
 # Grouping Data Overview
 
-In Telerik Reporting, data items can aggregate and summarize data, display it in visual hierarchies, or create different views, thus helping the user/decision maker understand and analyze data in a more efficient manner.
+In Telerik Reporting, data items can aggregate and summarize data, display it in visual hierarchies, or create different views, thereby helping users and decision-makers understand and analyze data more efficiently.
 
-In Telerik Reporting, groups are named sets of data that are bound to a data item. You specify groups by defining their names and grouping criteria (expression).
+In Telerik Reporting, a group is a named set of data bound to a data item. You specify groups by defining their names and grouping criteria (expression).
 
-To create a grouping expression you add Grouping objects to the __Grouping__ collection. The set of group expressions can be a single data field reference or a combination of multiple expressions. At runtime, group expressions are combined and applied together to the data.
+To create a grouping expression, you add Grouping objects to the __Grouping__ collection. The set of group expressions can be a single data field reference or a combination of multiple expressions. At runtime, group expressions are combined and applied to the data.
+
+> Grouping values are __case-sensitive__.
 
 Depending on the grouping expressions, groups may be static, dynamic, or detailed:
 
-* __Static groups__ are defined by empty (no) expression or expression that evaluates to the same value, disregarding the data (ex.: `=1 + 2`). Static groups always produce a single member that contains all the data.
-* __Dynamic groups__ are defined by expressions that produce different results according to the current data (ex.: =Fields.County). This way the items of the data source are partitioned into groups according to the values of the grouping expressions.
+* __Static groups__ are defined by an empty (no) expression or expression that evaluates to the same value, disregarding the data (ex., `=1 + 2`). Static groups always produce a single member that contains all the data.
+* __Dynamic groups__ are defined by expressions that produce different results according to the current data (ex., `=Fields.County`). This way, the items of the data source are partitioned into groups according to the values of the grouping expressions.
 * __Details groups__ are defined by a single __Grouping__ object that has no expression (empty __Grouping__ ) and produces one member for each item of the data source. Detail groups can be applied to __Table__, __Crosstab__ or __List__ items; *for backward compatibility reasons, the Report item treats the detail groups as static groups*.
 
 Groups support filtering and sorting that allows you to limit and order the members of the group according to your needs. For more information see [Filtering Data]({%slug telerikreporting/designing-reports/connecting-to-data/data-items/filtering-data/overview%}) and [Ordering Data]({%slug telerikreporting/designing-reports/connecting-to-data/data-items/ordering-data/overview%}).
 
 Groups are internally organized as members of one or more hierarchies for each data item. A group hierarchy has parent/child groups that are nested and can have adjacent groups. As groups have names, the group hierarchy defines the named scope hierarchy for the report items and expressions.
 
-Data items support groups in different manners according to their structure and application. The following list summarizes how the data items work with groups:
+Data items support groups in different ways according to their structure and application. The following list summarizes how the data items work with groups:
 
-* __Report__ – Report groups are defined by adding __Group__ objects to the report’s __Groups__ collection. Report groups are always nested according to the order in the __Groups__ collection. To display group data one should use the __GroupHeaderSection__ and __GroupFooterSection__ that appear once for each group member, respectively at start and end. The __DetailSection__ displays detailed data in a report and always appears inside the innermost group (if any).
-* __Table item__ – If you think of the parent/ child groups as a tree structure, each group hierarchy is a forest of tree structures. The __Table__ data item includes row and column group hierarchies. Data associated with row group members expand horizontally across the page and data associated with column group members expand vertically down the page. __The Group Explorer__ tool window displays row group and column group members for the currently selected __Table__ data item on the design surface. To create a group one should create a __TableGroup__ object and add it to the corresponding group hierarchy. According to their different specialization, the three derivatives of the __Table__ item works with groups in a different manner:
+* __Report__ – Report groups are defined by adding __Group__ objects to the report’s __Groups__ collection. Report groups are always nested according to the order in the __Groups__ collection. To display group data, one should use the __GroupHeaderSection__ and __GroupFooterSection__ that appear once for each group member, respectively at the start and end. The __DetailSection__ displays detailed data in a report and always appears inside the innermost group (if any).
+* __Table item__ – If you think of the parent/ child groups as a tree structure, each group hierarchy is a forest of tree structures. The __Table__ data item includes row and column group hierarchies. Data associated with row group members expands horizontally across the page, and data associated with column group members expands vertically down the page. __The Group Explorer__ tool window displays row group and column group members for the currently selected __Table__ data item on the design surface. To create a group, one should create a __TableGroup__ object and add it to the corresponding group hierarchy. According to their different specialization, the three derivatives of the __Table__ item work with groups in a different manner:
 
 	* __Table__ – define nested row groups and adjacent row groups. By default, a table includes a details group.
 	* __Crosstab__ – define nested row and column groups, and adjacent row and column groups.