HTML declarations 

Vue allows you to use HTML tags and attributes to control and alter the view of your application. This involves setting attributes dynamically, such as alt and href. It also allows you to render tags and components based on data in the application. These attributes begin with a v- and, as mentioned at the beginning of this book, get removed from the HTML on render. Before we start outputting and filtering our data, we'll run through a few of the common declarations.