There are three selection modes: Hierarchy, Object and Component. You use these modes in order to limit or mask the selection of other objects in order to select only the types of items you want: top level of node hierarchies, complete objects, or object components. When you use a selection mask you are filtering out or masking items you don’t want to be chosen as part of the selection.
The icons for the three modes appear on the Status Line.
When you first start Maya, the selection mode is set to Object. This is useful for much of your selection work with Maya, with a few exceptions. When you want to select items that have been grouped, set the selection mode to Hierarchy.
If you set the selection mask, it will remain that way until you change it again. If an item won’t select for you in Maya, you should check the selection mask setting to see if it is set correctly.
You can also select components in Soft Selection mode - see Select objects or components.
