What is the difference between Bootstrap and Bootstrap 3?
|1.||No support for panels.||Support added with a host of classes for panels|
|2.||Form actions||Dropped support for form actions.|
|3.||Gridless than 768px not supported.||Extra-small (less than 768px) are now supported.|
|4.||Only “.alert” class for the danger||Added “danger” and “warning” class.|