Answer / nazrul

user control
1)it extension is .ascx.
2)it can be more than one on single web page.
3)it doesn't contain Contentplaceholder.
4)it doesn't work like a fixed template.it can be
display in diffrent manner in diffrent page.
MasterPage:
1) it extension is .Master.
2)it used like a template.
3)it contain ContentPlaceHolder.

Answer / venkatesh

Both are code reduce features and reusability Purpose.When
we create Masterpage that is common to overall
project,whereas user controls these r used when we have
requirement on specific criteria.
Master page ex: INBOX,SPAM,DRAFT,TRASH etc in YAHOO WEBSITE

Answer / jiten

Master has a conteact plceholder where u can put child page
in this cph.

when user control is uses with in page . u can not use any
page in user control

Answer / vdk

Master pages and user controils are two different concepts.

Master pages are used to provide the consistent layout and
common behaviour for multiple pages in your
applications.then u can add the Contenetplaceholder to add
child pages custom contenet.
User Controls:Sometimes u need the functionality in ur web
pages which is not possible using the Built-In Web server
controls then user can create his own controls called user
controls using asp.net builtin controls.User controlsn are
those with .aspx extensions and u can share it in the
application.

Answer / surender sardana

I Think Both are same but key difference is that , we can
not use mater page in user control................

Answer / ashish

master pages can not be cached.
user controls can be cached .

Answer / shaik mujahid

Master page inherits all child pages in contentplace holder
and usercontrol can be placed in master page

user control is a control which must be placed in a page to
perform specific task

Answer / jay

just a not :
this can be a tricky question depending on the interviewer.
Masterpage IS a UserControl, and you can easily check this
either by exploring classes to which websites are being
compiled or simply noting :
public class MasterPage : UserControl

semanticaly, use of classical UserControl and Masterpage is
of course different, but this already has been elaborated in
other answers

Answer / sandeep

Master page is just like a template and can be
reuse.

User Control provides structure,reuse ability and functionality

Answer / vimal katiyar

Master Page
1-extension .master
2- provide fixed layout and common behaviour in all
page of website
3-it contains content place holder
4-not contain cached

user control
1- .ascx
2- not fixed provide layout in each page
3- we use in master page also
4- not contain content placeholder

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