Benefits of automation testing:

1. Speed: Think about how long it would take you to manually try a few thousand test cases for the windows Calculator. You might average a test case every five seconds or so. Automation might be able to run 10, 100 even 1000 times that fast.
2. Efficiency: While you are busy running test cases, you can’t be doing anything else. If you have a test tool that reduces the time it takes for you to run your tests, you have more time for test planning and thinking up new tests.
3. Accuracy and Precision: After trying a few hundred cases, your attention may reduce and you will start to make mistakes .A test tool will perform the same test and check the result perfectly, each and every time.
4. Resource Reduction: Sometimes it can be physically impossible to perform a certain test case. The number of people or the amount of equipment required to create the test condition could be prohibitive. A test tool can used to simulate the real world and greatly reduce the physical resources necessary to perform the testing.
5. Simulation and Emulation: Test tools are used to replace hardware or software that would normally interface to your product. This “face” device or application can then be used to drive or respond to your software in ways that you choose-and ways that might otherwise be difficult to achieve.
6. Relentlessness: Test tool and automation never tire or give up. It will continuously test the software.

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Benefits of Automation Testing are:

1. Save Time /Speed: Due to advanced computing facilities, automation test tools prevail in speed of processing the tests. Automation saves time as software can execute test cases faster than human.
2. Reduces the tester’s involvement in executing tests: It relieves the testers to do some other work.
3. Repeatability/Consistency: The same tests can be re-run in exactly the same manner eliminating the risk of human errors such as testers forgetting their exact actions, intentionally omitting steps from the test scripts, missing out steps from the test script, all of which can result in either defects not being identified or the reporting of invalid bugs (which can again, be time consuming for both developers and testers to reproduce)
4. Simulated Testing: Automated tools can create many concurrent virtual users/data and effectively test the project in the test environment before releasing the product.
5. Test case design: Automated tools can be used to design test cases also. Through automation, better coverage can be guaranteed than if done manually.
6. Reusable: The automated tests can be reused on different versions of the