There is a definite difference in Unit testing and White Box Testing.
****************************************************************************
Unit Testing >>>>includes White box testing and Black Box Testing

White Box Testing >>>>relates only to the checking of Internal Code.

Plz go thru the explanation below and I hope it helps you t
understand
************************************************************************************************
Unit Testing :- is done at the first stage of programming when th
developer checks first to see if entered code is functioning for th
single unit developed. At this stage the developer may do white bo
Testing (Internal Code review ) as well as Black Box Testing
Functionality) Testing to determine that what is there on the interfac
( GUI) is in synch with the backend ( Database). Only after th
developer is satisfied does this come to the Testing dept to do Whit
\\Black Box Testing.
************************************************************************************************
White Box Testing is also known as Structural, Open Box, Clear box o
Glass box testing.

Here explicitly the internal code is checked. Testing input/output wit
full knowledge and/or regard of the internal code. Commonly
designed/executed by the Developers.
In the White Box testing there is more concern about the internal logi
of the program i.e.; here we check module interface, local dat
structures, logical conditions on their true and false side, loop
etc;

It is a software testing technique in which an explicit knowledge o
the internal workings
of the item to be checked is to be tested.
White box testing is a test case design method that uses the contro
structure of the
procedural design to derive test cases.
Test cases can be derived that

o Guarantee that all independent paths within a module have bee
exercised at least once
o Exercise all logical decisions on their true and false sides,
o Execute all loops at their boundaries & within their operationa
bound

-----------------------------------------------------------------------
IT Interview Questions : http://www.geekinterview.com <br> Tutorials and Articles : http://www.geekarticles.com <br> Free Training : http://www.exforsys.com