As you can see by the title, ASP is an acronym for Active Server Pages.

ASP is developed by Microsoft. It is not really a standard ASP is neither a real programming language nor is it a programming language, but it's a Microsoft technology that lets you use so-called scripting in your documents.

To describe what an ASP page is, you could say that it is a file with the extension .asp that contains a combination of HTML tags and scripts that run on a web server.