Using Angular markup like {{hash}} in a src attribute doesn't
work right: The browser will fetch from the URL with the literal
text {{hash}} until Angular replaces the expression inside
{{hash}}. The ngSrc directive solves this problem.
The buggy way to write it:
<img src="http://www.gravatar.com/avatar/{{hash}}" alt="Description"/>
The correct way to write it:
<img ng-src="http://www.gravatar.com/avatar/{{hash}}" alt="Description" />
<IMG
  ng-src="template">
...
</IMG>
      | Param | Type | Details | 
|---|---|---|
| ngSrc | template | 
         any string which can contain   |