Size Large Add this class .btn-lg
Active state Add this class .active
Disabled state Add this disabled="disabled"
Dropup variation Trigger dropdown menus above elements by adding .dropup to the parent.
Block Level Buttons Add this class .btn-block
Button toolbar Combine sets of <div class="btn-group"> into a <div class="btn-toolbar"> for more complex components.
Nesting Place a .btn-group within another .btn-group when you want dropdown menus mixed with a series of buttons.

Info Web

Size Small Add this class .btn-sm
Size Extra Small Add this class .btn-xs
Split button dropdowns Similarly, create split button dropdowns with the same markup changes, only with a separate button.
Buttons group Wrap a series of buttons with .btn in .btn-group