Angularjs Learning Note II (Display and hiding of DOM elements)

DOM element display and hiding, is the front-end development is often used in the function, Angularjs is the use of ng-hide/ng-show two properties to achieve the fact that we just use one of these properties to achieve all the functionality of their value is Boolean.

"HTML code"

<! DOCTYPE html>

（But there is a problem: it is when I set the $scope directly. But.show variable when there are a lot of errors, is not allowed to set the variable? 
a great God who knows can comment, thank you )

Angularjs Learning Note II (Display and hiding of DOM elements)