A shortcode is a WordPress-specific code that lets you do nifty things with very little effort. Shortcodes can embed files or create objects that would normally require lots of complicated, ugly code in just one line. Shortcode = shortcut

And here is how you can use shortcode in Masterdigm API Plugin

How to locate shortcode? when adding Page you can see a shortcode in the editor, the name of the shortcode is “Masterdigm API”