Threat Modeling is to identify potential threats which could harm your business. It can give you idea on how to build a solid security strategy against potential threats.
In order to understand your application context, you must understand the individual elements that, together, create it. Defining the various elements of your application individually enables each element to be analyzed and coupled together to define an application context. This makes it possible to identify potential threats, and then systematically build an effective security strategy.
Please see the below video for the introduction to the application.