Difference between adhoc testing,monkey testing and exploratory testing

Adhoc testing: This Kind of testing dosen't have a any process/test case/Test senarios defined/preplanned to do it.It involves simultaneous test design and test execution.

Monkey testing:-monkey testing is a testing that runs with no specific test in mind. The monkey in this case is the producer of any input data (whether that be file data, or input device data).
Keep pressing some keys randomely and check whether the software fails or not.

Exploratory testing is simultaneous learning, test design and test execution.It is a type of adhoc testing, but here the tester does not have much idea about the application, he explores the system in an attempt to learn the application and simultaneously test it