Exploratory Testing: Exploratory Testing can be a creative, 
informal software test that is not based on formal test 
plans or test cases, testers may be learning the software 
as they test it.

Ad-hoc testing: Ad-hoc testing is similar to exploratory 
testing, but often taken to mean that the testers have 
significant understanding of the software before testing it.

Ad-Hoc testing ,generally every testing team conducts 
formaltesting  on the build ,in some situations like lack 
of time ,lack of domain knowledge and lack of documentation 
testing team conducts informal testing they concentrates on 
the main functionalities this is called 'adhoc testing'
Exploratory testing comes under the catagory of adhoc 
testing ,testing conducted by the testing team with out any 
documents is called 'Exploaratory testing'.

Exploratory teting: In this testing testing engg., retting 
100% knowledge in that application testing engg., are 
previous knwledge,internet browsing,team disccusions,vedio 
conference with customers and avilable documention tet engg 
are concentrating on system testing.This style of testing 
is also called as artistic testing.
 
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