What is ASP/ASP.NET?
ASP means Active Server Pages, a Microsoft development that allows building dynamic web applications. The ASP-code is applied on a Windows server. The current version is 4.7.1
ASP.NET is the newest development and uses the Microsoft .NET platform. This enables an object-oriented approach through e.g. C# and VB.NET. Meanwhile is available here https://dotnet.microsoft.com/apps/aspnet.