There is very often a need to manipulate set of objects as a single one. You can join selected objects into the one using group option. Select objects that are going form the group by clicking on each one with SHIFT key held down in work area or in Scene objects list. Currently selected objects are highlighted in yellow on the Scene objects list. In work area each selected object is surrounded by a yellow bounding box. To join them into the group press CTRL+G or click group icon .
As you can see on the figure above after grouping other icons become active - you can ungroup or modify the content of the group .
The group can be animated as a single object. It has own keys for move, rotate and scale. However you can also animate member of the group individually. Members of the group are displaying shifted a bit to the right in scene objects list and timeline list. Both the group and its members have their own tracks for keys.
The example below shows the group of 6 boxes moving around the center of the group while one of them is scaling up and down and other is moving to the centre of the group and back.
You can easy add another object from scene to existing group by modifying group content even when group has already animation keys. It will be joined as a part of the group and follow the group if it's in motion.
Groups can be grouped into another ones. Also groups can be joined with single objects. There is no limit of the depth for created structure. The screenshot below shows the example of 3-level structure.
Selecting groups and its members
In order to select any item on Scene objects list just click left mouse button on it. Hold SHIFT key if you want to add it to current selection. In the main view select particular items with right mouse button. Holding SHIFT causes adding to selection and holding CTRL switches through available group levels that clicked item belongs to.