Re-Testing means ones all bugs are fixing from "bug report",
we are doing the testing for that report,all bugs are fixed
or not?
The retesting is mostly focused on that particular module.
that means in which module we are finding the errors on that
module only we are concentrating and we have to check for
that module only.
Regression Testing:This one is also depending upon "Bug
Report" only.But in regression Testing we are concentrating
on total application
That means:newly fixed bugs were effected in any other
place(like in any other modules)or not this is called
regressiion
Re-testing done by manually
Regression testing done by automation.

regression testing: when ever change is made in the sorce 
code we are handle in the regression testing . ex add new 
application in the source code 
re-testing:testing conducted on a particular bug when its 
been fixed

when a developer fix the bug and send the modified build to
a tester, first tester do Re-testing on that module or
application. Re-testing means, testing the module whether
the bug is fixed or not with multiple sets of data.. then 

Regression testing : when the tester come's to conformation
that the big is fixed, then he starts Regression testing on
that modified build. in this testing, the tester test's or
checks whether the modified build is showing any impact on
other application or not.. means whether new application or
functionality is effecting other application or not.the
tester checks after fixation of bug,we got any side effects
in application or not... 

why because , during the bug fixing some parts of coding may
be changed or functionality mat be manipulated.. in this
case the old test cases will up-dated or completely
re-written according to new feauter of application where bug
fixed area..... 

if any mistake pls correct me .. tank u every body

priyan
priyanonlyone@gmail.com

Re-Testing: testing the build/ application multiple times
with the same set of Test Cases and the Test Data, which was
used for testing the same application for the first time.

Regression Testing: Testing the new build/ application when
some new functionality is added to the system. This type of
testing usually done to see that the added functionality do
not affect the functionality of the build which was already
tested.

Hi,
retesting and regression testing both are different-
Retesting is means if nay change in system software or h/w
we need a retesting of the application.and will check the
all data is same working the second time or not?

Regression Testing means if any change will happen the
development side we need the regression testing.and we will
check the all functionality of the system properly.as well
as requirement.   thanks
if any suggestion plz let me know welcome for your suggestion
or mail me-qazijk@yahoo.com

Re-testing - testing a reported bug 
to verify that it has been fixed.

Reggression testing - testing the 
entire application to ensure that it 
has not been affected in anyway 
due to fixing of the reported bug.