According to Wikipedia Model–view–viewmodel (MVVM) is a software architectural pattern.

MVVM facilitates a separation of development of the graphical user interface be it via a markup language or GUI code from development of the business logic or back-end logic (the data model). The view model of MVVM is a value converted ,meaning the view model is responsible for exposing (converting) the data objects from the model in such a way that objects are easily managed and presented.


View
The view is responsible for defining the structure, layout, and appearance of what the user sees on the screen.It is in xaml



Model
The model in MVVM is an implementation of the application's domain model that includes a data model along with business and validation logic. (get, set)



View Model
The view model acts as an intermediary between the view and the model, and is responsible for handling the view logic.

More
https://www.tutorialspoint.com/mvvm/


https://www.tutorialspoint.com/windows10_development/index.htm

https://blogs.msdn.microsoft.com/msgulfcommunity/2013/03/13/understanding-the-basics-of-mvvm-design-pattern/
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