Getting the error: Bootstrap's JavaScript requires jQuery version 1.9.1 or higher. What that means?

Question

Often developing on Wordpress site, there could be an error shown as below:

Uncaught Error: Bootstrap's JavaScript requires jQuery version 1.9.1 or higher, but lower than version 3

Answer

On new Wordpress install, Wordpress installed the new jQuery version 3.  If you are using an old theme or plugin, the bootstrap coding might not be compatible with the jQuery version provided by Wordpress.  

In order to resolve this, you must ensure the theme/plugins are up-to-date and is compatible with jQuery 3.