String interpolation and property binding are parts of data-binding in Angular. Data-binding is a feature of Angular, which is used to provide a way to communicate between the component (Model) and its view (HTML template). There are two ways of data binding, one-way data binding, and two-way data binding. In Angular, data from the component can be inserted inside the HTML template. Any changes in the component will directly reflect inside the HTML template in one-way binding, but vice-versa is not possible. On the other hand, it is possible in two-way binding.

String interpolation and property binding both are examples of one-way data binding. They allow only one-way data binding.

String Interpolation: String interpolation uses the double curly braces {{ }} to display data from the component. Angular automatically runs the expression written inside the curly braces. For example, {{ 5+5 }} will be evaluated by Angular, and the output will be 10. This output will be displayed inside the HTML template.

Property Binding: Property binding is used to bind the DOM properties of an HTML element to a component's property. In property binding, we use the square brackets [ ] syntax.