This article is about using Vonage's Number Insight Basic API to retrieve basic information about a phone number within an ASP.NET web application. It guides developers through setting up the application, creating a view for users to input a phone number, and making a call to the Number Insight Basic API to retrieve international and national formats, country of registration, and more. The article concludes by showcasing how this information can be displayed on a view within the ASP.NET app.