What is interpolation?

Interpolation is a special syntax that Angular converts into property binding. It’s a convenient alternative to property binding. It is represented by double curly braces({{}}). The text between the braces is often the name of a component property. Angular replaces that name with the string value of the corresponding component property.

Let's take an example,

<h3>
  {{title}}
  <img src="{{url}}" style="height:30px" />
</h3>

In the example above, Angular evaluates the title and url properties and fills in the blanks, first displaying a bold application title and then a URL.