1)Severity is interms applcation where as priority is 
interms of customer requirements.

when we are conducting testing if  a bug is found and due 
to that we are not able to move to conduct testing then we 
are going to assign the severity as high.

where as suppose lets consider the password field, its 
visible to people but that defect is having priority as 
high interms of customer point of view,but there we can 
able to move to conduct tetsing but is having priority as 
high..

2)we can launch client server applications directly
where as to launch a web based applications we need lauch 
data base server ,web server then only we can able to 
launch the our web based application thru a internet 
explorer using URL
   client server applications are menu driven where as web 
based applications are links driven
    client server applications are less content when 
compared to web based applications,bcz they contain more 
content as paragraphs and as images.

3)Bug life cycle:it mainly contains the status like
New-Assigned-open-fixed-closed  or
new-Assigned-defered(Post poned)
New-Assinged-Rejected (Lack of clarity ) or
New-assigned-reopened-fixed-closed

Bug Priority will be decided by development Team lead or 
Project Manager not by Test Engineer.
Priority depeds on BUsiness Importence of bug

Severity will be decided by the test engineer based on
failure of certain feature of application under test.
Severity depends on How failed  test condition affets the 
application functionality.

Web Based Application:
Browser acts as client to access the application from 
remote server.
Windows application will be installed in the same system.

byee
Rajendra 
rajendra_penumalli@yahoo.com