“Automation is a part, but Manual is Heart of testing”
Manual software testing is the process where each individual part of software is verified by a tester, without using any script or tool and compared with the expected results, in order to find the defects (also called bugs) of the software.
Basically, using manual testing, the tester can see and use the software as a user would, which could be a very important factor for development, as the tester could also give improvements and ideas that would make a smooth user experience.
