ASMX

An ASMX file is a server-side script file used in Microsoft's ASP.NET framework to create web services. These files are essentially XML documents that contain code, typically written in C# or Visual Basic .NET, defining the logic for the web service. When a client makes a request to an ASMX file, the ASP.NET runtime processes the code within the file and returns a response, usually in XML or JSON format.

Web services created with ASMX files allow different applications, potentially running on different platforms, to communicate with each other over the internet. They achieve this by exposing methods that can be called remotely. This makes ASMX files a foundational technology for building distributed applications and enabling interoperability between systems.

The ASMX architecture leverages the Simple Object Access Protocol (SOAP) by default, although it can also be configured to support other protocols. While ASMX has been a popular choice for web services, newer technologies like Windows Communication Foundation (WCF) and ASP.NET Web API offer more flexibility and advanced features for building web services and APIs. However, ASMX files remain in use in many existing applications.