in Adhoc testing we test the software randomly and in this
testing test cases are required.but in exploratory  testing
we test the software randomly there is no need of test
cases.this is the main difference.

Exploratory testing is testing of an unfamiliar 
applications. The test scripts would not be prepared before 
hand. Test case design and execution are done concurrently. 
Adhoc testing is intended to look for defects randomly. 
This can be carried out by any one by Exploratory testing 
is a thoughtful approach and driven by logic. It is an 
intellectually challenging process where one is limited by 
one's own imagination and understanding of the software 
being tested. It provides enough scope to extend the reach 
of testing to certain areas that cannot be easily 
accomodatedin test cases.

Adhoc testing:
              If there is no proper testplan at that time 
we can perform adhoc testing.It has some sample test cases.

Exploratory testing:
                    If there is no test plan we can study 
the SRS (Requirements documents) at that time,and 
simulteneously we can perform testing.This is commonly 
called as exploratory testing

Muralidharan

dharanmu@yahoo.com

AD HOC TESTING-:TESTING THE PRODUCT WITHOUT FOLLOWING ANY 
TEST SPECIFICATIONS BY FOLLOWING FUNCTIONALITY OF THE 
PRODUCTS.ITS DONE BY DOMAIN EXPERTS.
EXPLORATORY TESTING-:TESTING THE PRODUCT WITHOUT FOLLOWING 
ANY TEST SPECIFICATIONS AND WITHOUT FOLLOWING 
FUNCTIONALITY .

Adhoc Testing:Testing carried out informally,no formal test 
preparation takes place,no recognixed test design technique 
is used, there are no expectations for results and 
guidelines for the test execution activity.
Exploratory Testing:Is a approach in whic testers r 
involved in minimum planning and maxmium execution.
The test design and test execution activities are performed 
in parallel typically without formally documenting the test 
conditions,test cases or test scripts.
Useful when there are no or poor specifications and when 
time is severly limited

exploratory testing is often taken to mean acreative 
informal software test that is not based on formal test 
plans or test cases testers may be learning the software as 
they it
Similar to exploratory testing but tester will learn before 
going to test is adhoc testing

Adhoc Testing :
      This type of testing is done without any formal Test 
Plan or Test Case creation. Adhoc Testing helps in deciding 
the scope and duration of the various other testing and it 
also helps testers in learning the application prior 
starting with any other testing.

Exploratory Testing :
       This testing is similar to the adhoc testing and is 
done in order to learn/explore the application.

In my opinion, most of the answers here appear to be
misguiding because a) they do not know who coined the term
/exploratory testing/ and who practice it, who research on
it and who teaches them.

Dr Cem Kaner coined the term Exploratory Testing somewhere
around 1980 although people were doing it much before that
without having a name to it.

The latest update about the definition of Exploratory
Testing from the man who coined it can be accessed in this
link : http://www.satisfice.com/kaner/?p=42 and quoting from
that 

/“Exploratory software testing is a style of software
testing that emphasizes the personal freedom and
responsibility of the individual tester to continually
optimize the value of her work by treating test-related
learning, test design, test execution, and test result
interpretation as mutually supportive activities that run in
parallel throughout the project.”//

Now, that looks like a complex memorization puzzle to many
testers and hence they attempt to provide a concise
definition or often plagiarizing it.

Not owing credits to the man who has been working on it or
to men who have been working on it for a long time is an
extremely bad idea and the biggest harm to the community.

Saying that - I do not mean you should not be coining
another definition of your own but the fact is hardly anyone
who have their own definitions get it tested enough.

For instance, if you are introducing a new definition of
testing, would you bother to check it up with other people
who have been researching on it? Probably not because you
are free to think anything you want or create more chaos to
existing stuff.

The interesting thing is most interviewers also fail to
recognize the so called correct definition of exploratory
testing. If Dr Cem Kaner was a candidate in one of the
interviews, the interviewer would blindly reject the
definition that Dr Cem Kaner says on exploratory testing
unless the interviewer identified Cem Kaner and his work.

So, we are in a chaos and that's not a problem compared to
our mindset of being happy with the chaos. The advantage for
poor thinking minds is they shine as much as others do in a
chaotic environment and that's probably why you and me have
a job today.

-- Pradeep Soundararajan -- http://testertested.blogspot.com
- http://www.viddler.com/explore/testertested