As a tester, it is always advisable to use manual white box testing and black-box testing techniques on the test software. Manual testing helps discover and record any software bugs or discrepancies related to the functionality of the product.

Manual testing can be replaced by test automation. It is possible to record and playback manual steps and write automated test script(s) using Test automation tools. Although, test automation tools will only help execute test scripts written primarily for executing a particular specification and functionality. Test automation tools lack the ability of decision-making and recording any unscripted discrepancies during program execution. It is recommended that one should perform manual testing of the entire product at least a couple of times before actually deciding to automate the more mundane activities of the product.

Manual testing helps discover defects related to the usability testing and GUI testing area. While performing manual tests the software application can be validated whether it meets the various standards defined for effective and efficient usage and accessibility. For example, the standard location of the OK button on a screen is on the left and of CANCEL button on the right. During manual testing you might discover that on some screen, it is not. This is a new defect related to the usability of the screen. In addition, there could be many cases where the GUI is not displayed correctly and the basic functionality of the program is correct. Such bugs are not detectable using test automation tools.

Repetitive manual testing can be difficult to perform on large software applications or applications having very large data set coverage. This drawback is compensated for by using manual black-box testing techniques including equivalence partitioning and boundary value analysis. Using which, the vast dataset specifications can be divided and converted into a more manageable and achievable set of test suites.

A manual tester would typically perform the following steps for manual testing:

1. Understand the functionality and requirement of product
2. Prepare a test environment
3. Execute test case(s) manually
4. Verify the actual result
5. Record the result as Pass or Fail
6. Make a summary report of the Pass and Fail test cases
7. Publish the report
8. Record any new defects uncovered during the test case execution

There is no complete substitute for manual testing. Manual testing is crucial for testing software applications more thoroughly. Test automation has become a necessity mainly due to shorter deadlines for performing test activities, such as regression testing, performance testing, and load testing