ASP.NET is Microsoft’s open source server-side website application framework. It is designed mainly for creating dynamic web pages offering programming model, comprehensive software infrastructure and various services needed to build a robust web app for your desktop as well as mobile devices.
ASP.NET applications are compiled codes written in extensible and reusable components or objects present in the .NET framework. ASP.NET are written in either of the following languages:
Visual Basic .NET
So if you know any of these programming languages, then you can create a web application using ASP.NET.
To get you started, here’s a video on how to create your first ASP.NET.