ASP.NET vs PHP

It is quite normal that people has confusion between ASP.NET and PHP. In fact, ASP.NET is a subset of .NET Framework and PHP is a server site programming language. At the end, they may take part in developing web application but there are not the same.

.NET Framework is a big set of classes and libraries that have been created for developing all sorts of application; such as Windows Standalone Application, Dynamic Link Library or Web Application. And, ASP.NET is a subset of this "big family". ASP.NET contains classes and libraries that related to web development.

.NET Framework consists of two parts; Framework Class Library and Common Language Runtime. In fact, it is quite similar to JAVA. The concept behind .NET Framework is to build a cross architecture application that will split the process into compiling and running code in two different mode. Let take a look at the JAVA work flow diagram.

A JAVA source code with file extension of .java is compiled into a bytecodes file with file extension of .class. And the .class object file can be executed by JVM (Java Interpreter). It is a great concept from JAVA creator to separate the code from the machine. Thus, the task of communicating with different type of CPU architecture has been passed to JVM and class file will be able to run on different type of platform without modifying the source code and re-compilation depend on architecture is not needed.

In .NET, the similar concept is adapted in order to achieve this. Let take a look at the diagram above. It is a typical process of a .NET workflow. The source code will be compiled into MSIL (Microsoft Intermediate Language). And upon execution, it will be compiled by JIT compiler, resided in .NET engine, into a native code that can be executed by that particular machine.

For ASP.NET, the common programming language being used are C# and VB.NET. The source code of these program will be compiled by different language compiler (as C# source code can be only understood by C# compiler) stated in the page directive of the top of the aspx file. This will generate a Intermediate Language file. Then, it will be executed after compile by JIT into a native code.

I hope it will be useful to those person who just wanted to start to learn .NET or ASP.NET development. In short, you may compare C# with ASP.NET vs PHP but not ASP.NET vs PHP.