File Types in ASP.NET 4.0 Web Applications

You already know , web applications contain numerous file types.This is supported and managed by the IIS Server or ASP.NET Applications.Generally, most of the file types can be generated using the Add New Dialog box in visual studio 2010.These file types is more important to you because they are helpful to understand the codes and behavior of the file. ASP.NET 4.0 supported many file types which we will see latter. All File types are mapped to web applications using application mappings. For Example if we open .txt file then it opens in Notepad by default because window .txt file directly mapped to the Notepad.exe file. All .NET Developers should know about these extension files and its usages. 
There are some file types managed by ASP.NET as given below:-

1.)  .asax  --> It refers to the Global.asax file containing code that drives from the HttpApplication class.It resides Application root directory.
2.) .ascx  --> It refers to a web user control file. It resides Application root directory or a subdirectory.
3.) .aspx  --> It refers to a ASP.NET Web forms.It resides Application root directory or a subdirectory.

4.) .asmx  --> It refers to an xml web services file that contains classes and methods. It resides Application root directory or a subdirectory.
5.) .axd  --> It refers to a handler file that is used to website administration requests.It resides Application root directory.
6.) .cd  --> It refers to a class diagram file. It resides Application root directory or a subdirectory.
7.) .compile  --> It refers to a precompiled stub file that point to an assembly representing a compiled website file.Fir example .aspx,.ascx ,.master file are precompiled. It resides Bin subdirectory.
 8.) .browser  --> It refers to a browser definition file used to identify the features of client browsers. It redies App_Browsers Subdirectory.
9.) .dll  --> It refers to a compiled class library files (assembly file).It resides Bin subdirectory.
10.) .cs,.vb,.jsl  --> It refers to a Source -code file that contains application logic.It resides App_Code Subdirectory or same directory as web page.
11.) .csproj,.vbproj,.vjsproj  --> It refers to a project file for a visual studio client application project.It resides Project Directory of visual studio.
12.) .master  --> It refers to a master page that defines the layout of web page in a web application.It resides Application root or subdirectory.
13.) .mdf,.sdf  --> It refers to a SQL database file. It resides App_Data subdirectory.
14.) .mdb,ldb  --> It refers to a Access database file. It resides App_Data subdirectory.
15.) .msgx,svc  --> It refers to an indigo messaging framework (MFx) service file.It resides  Application root or a subdirectory. 
16.) .disco,.vsdisco  --> It refers to a xml web services discovery file.It resides App_WebReferences subdirectory.
17.) .dsdgm, .dsprototype  --> It refers to a distributed services diagram file that can be added to any visual studio solution.It resides  Application root or a subdirectory. 
18.) .licx, .webinfo  --> It refers to a license file. It resides  Application root or a subdirectory. 
19.) .soap  --> It refers to a SOAP extension file .It resides  Application root or a subdirectory. 
20.) .sin  --> It refers to a Solution file for visual web developer project. it resides Visual web Developer project directory.  
21.) .skin  --> It refers to a skin file.It is used for consistent formatting in web controls. It resides App_Themes subdirectory.
22.) .sitemap --> It refers to a site-map file that containing the structure of the website. It resides Application root directory.
23.) .rem --> It refers to a handler file which implements remoting concepts in web application.It resides  Application root or a subdirectory. 
24.) .sdm , .sdmDocument --> It refers to a system definition model file.It resides  Application root or a subdirectory. 
25.) .resx , .resources --> it refers to a resource file that containing resource strings. It resides App_GlobalResources or App_LocalResources subdirectory.