Selecting

Selection in Pose Mode is very similar to the one in Edit Mode, with a few specificities:

You can only select whole bones in Pose Mode, not roots/tips...

Grouped

You can select bones based on their group and/or layer, through the Select Grouped pop-up menu Shift-G:

• To select all bones belonging to the same group(s) as the selected ones, use the In Same Group entry Shift-G-Numpad1.
• To select all bones belonging to the same layer(s) as the selected ones, use the In Same Layer entry Shift-G-Numpad2.