The process carried out to test the software defects manually without using any automated tool or script is know as manual testing.
In such testing tester plays a role of end an user and test the software application by using all features of the software application to identify bugs and defects.
Hence we can say that, It is very basic and preliminary testing which helps to ensures and finds out the defects and the bugs in the application.
So software tester have to use test plan, test cases to test the software to ensure whether testing was plenitude or not.
Manual testing have different stages which are stated below:
Unit Testing: Unit Testing is first level of software testing process where every single unit or component of a software application are tested by software developers themselves by looking through narrowed eyes. This process is performed by using the White Box Testing method earlier then Integration Testing. Unit Testing is normally performed. In few or some cases it may also be performed by independent software testers.
Integration testing: Integration Testing is a phase of software testing process where individual software modules and units are combined and tested as a group. It take place after unit testing and prior to system testing. The purpose of this level of testing is to expose faults in the interaction between integrated units. Hence Integration testing takes modules as its input that have been unit tested in prior phase, groups them in larger aggregates then applies tests defined in an integration test plan to those aggregates and delivers as its output the integrated system ready for system testing.
System testing: System Testing is a phase of software testing process where a complete, integrated system/software is tested. System testing is performed on the entire system. The purpose of this test is to evaluate the systems compliance with the specified requirements. System testing tests not only the design, but the behavior too and also the believed expectations of the customer.
User Acceptance testing: User Acceptance Testing (UAT) is the last phase of the software testing process, carried out before the software goes live. During UAT, actual software users test the software to make sure it can handle required tasks in real-world scenarios, according to specifications, hence it is the last chance for the customer to test the software and measure if its fit for the purpose. (UAT), it is also known as beta testing, application testing or end user testing. In other words we can say that, UAT is one of the final and critical software project procedures performed when functional, system and regression testing is completed, also it must occur before newly developed software is rolled out to the market.