Our good old web application frameworks are based on the philosophies of MVC. Take the example of Django or Rails (Ruby): they structure their projects in the Model-View-Controller format except that it is represented as MTV (Model, Template, View) where the model is the database, templates are the views, and controllers are the views/routes.
As an example, let's take up the Tornado web application framework (http://www.tornadoweb.org/en/stable/) to develop a single-page app. This application is used to manage a user's tasks and the user has permissions to add tasks, update tasks, and delete tasks.
Let's see the design considerations:
Let's start with the controllers first. In Tornado, controllers have been defined as views/app routes. We need to define multiple views such as listing the tasks, creating new tasks, closing the tasks, and handling an operation if a request could not be served.
We should also define models, the database operations to list, create...