White Box Testing:Means testing the application with 
coding /programming knowledge.That means the tester has to 
correct the code also.

Black box testing:testing the application without 
coding /programming knowledge that means the tester doesn't 
require coding knowledge.Just he examines the appliaction 
external fucntional beheaviour and GUI features.

byee friends
Rajendra
rajendra_penumalli@yahoo.com

White box testing is done by the Developers. This requires
knowledge of the internal coding of the software. 

Black box testing is done by the professional testing team.
This does not require knowledge of internal coding of the
application. Testing the application against the
functionality of the application with out the knowledge of
internal coding of the software.

Whitebox Testing:It is done by developers.It typically 
involves in coding.In this Testing developers concentrates 
on internal structure of the program and justifgies whether 
that program is correct or not.
Blackbox testing: It is done by seperate Testing team. in 
this testers validates  the developed application by 
execution of testcases and finding Bugs and send error 
reports.

White box testing is nothing but coding.
It focus on the program part. Rather then finicality.
Black box testing is nothing but funcnality .
It focuses on the funcnality part rather then the program 
part.

In blackbox testing no knowledge of code is required and
with the little knowledge of the code thats called
'greybox'testing...



Whitbox testing that is related to structual knowledge
whereas Blackbox Testing that is related to funtional
knowledge.....

(1)Generally black box testing will begin early in the 
   software development i.e. in requirement gathering 
   phase itself. 
   But for white box testing approach one has to wait for  
   the designing has to complete.

2)We can use black testing strategy almost any size either 
  it may be small or large. 
  But white box testing will be effective only for small   
  lines of codes or piece of codes.

3)In white box testing we can not test Performance of the 
  application.
  But in Black box testing we can do it.


4 )In general we have to write large quantity of test 
   cases for whitebox. 
   But in black box its a selcection of sample test cases.