Fancy larger or smaller buttons? Add .btn-lg, .btn-sm, or .btn-xs for additional sizes.
Wrap a series of buttons with .btn in .btn-group.
Combine sets of <div class="btn-group"> into a <div class="btn-toolbar"> for more complex components.
Instead of applying button sizing classes to every button in a group, just add .btn-group-* to the .btn-group.
Place a .btn-group within another .btn-group when you want dropdown menus mixed with a series of buttons.
Just wrap a series of .btns in .btn-group.btn-group-justified.
Trigger dropdown menus above elements by adding .dropup to the parent.