I am trying my hands on Spring tool suite. I observed that it when you right click on your spring project and select run as then there are many options available out which two are
7 Maven build Alt+Shift+X,M
8 Maven build..
For me it look like one and the same thing. Still I am not able to figure out the difference between it.

The first one lets you pick an existing Maven launch configuration. The one with the
...opens a new launch configuration.