(we don't have any documentation for testing, i.e, we will 
test the project with out any Testcasecs, testing plane.)
similar to exploratory testing, but often taken to mean 
that the testers have significant understanding of the 
software before testing it. What is user acceptance 
testing - determining if software is satisfactory to an end-
user or customer.

testing an application without any testing strategy,

A process of testing whether we dont follow any particular
procedure . we know only functionality

checking only the important or outer module of the
application  to complete in time if the target to complete
the project is very near...

adhoc testing is an -ve testing in nature.Test engg tests 
the application randamly coz end users uses the application 
in an randam way.

Adhoc testing means which we test without test cases means
randomly we need to test.
Ex: If we don't have any documents for the new application
that time we will do explore and test.That test also called
Adhoc testing

Adhoc testing means: test engineers to test the application
according to without test cases,here ascertaining in  good
domain knowledge(functionality)peoples required.

it is non procedure way of testing
test casses are not prepared