Difference between Master Page & User Control in asp.net

[Samarth]

I am new user in asp.net. I am studying to make projects in asp.net(using .Net 2.0). I am having many .aspx pages. Every time when I want to create a new .aspx page, I have to create a basic html layout and then drag these user controls in the design mode. Should I use master pages.? I am bit confused in Master Page and the User Control. Can anyone tell me the what's the difference between the Master Page and the User Control.? Thanks in advance..!

[kelfro]

User Control :
Many times you need some functionality in your web pages, which is not possible to use it in Built-in Web Server Controls. Using this functionality user can create his own controls which is known as User Control that has been created using the asp.net controls. User control are nothing but .aspx extensions that can be shared in the application.

Master Pages :
Master pages are common to overall project. They are used to provide the consistent layout and common behaviour for the multiple pages in your
applications.

[Zecho]

Master Page is just like a template for your page. You get ready made code. And in User Control you can use other control anywhere according to you on your web page and can use any number of time. Like in one user control you can put more than one control. In short Master Page act as template and the merging container for the web pages whereas a User Control is control which can be used again in many pages.

[Praetor]

In master page you define the looks and standard behavior of your application. Master page works as a parent page. Using user control you can drag and drop every pages. So there is drawback of designing the repeated pages. Also with user control you can make assembly and can use another project also.

Caching is not performed in the master page and you cannot apply theme in your master page. Whereas you can apply theme and also can perform caching on user control.