What are block level buttons & active/disable buttons?

Block Level Buttons

A block level button spans the entire width of the parent element.
Add class .btn-block to create a block level button:

Example

<button type="button" class="btn btn-primary btn-block">Button 1</button>

Active/Disabled Buttons

A button can be set to an active (appear pressed) or a disabled (unclickable) state:
The class .active makes a button appear pressed, and the class .disabled makes a button unclickable:

Example

<button type="button" class="btn btn-primary active">Active Primary</button>
<button type="button" class="btn btn-primary disabled">Disabled Primary</button>