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.