test scenario describes a situation to prepare a testcase 
to test a specific functionality  correct if i am wrorng

A Test Scenario is a set of test cases covering the possible
ways of testing a set of conditions in its entirety (to the
fullest). A test script is a script which is intended to
perform a test as directed with a purpose of completing a task.

Test scenario will be framed on basis of the 
requrement,which need to be checked.For that,we will frame 
set of testcases,in other terms,we can say all the 
conditions,which can be determined the testing coverage 
againest business requirement.

Please see the below example,which is exactly matched to my 
explanation.

As we know all most all the application are having login 
screen,which contains login name and password.Here is the 
test scenario for login screen.

Scenario: USER'S LOGIN

Condtions to be checked to test the above scenario:
----------------------------------------------------
1.Test login field and Password fields indicisually.
2.Try to login with valid login and valid password.
2.Try to login with invaling login and valid pwd. 
etcc........................................


If I am wrong,please make comments againest my posted 
answer.

The test scenario is the situation prepared by the test 
team to execute a testcases.

Muralidharan
dharanmu@yahoo.com