Explain Integration Testing:

In Integration Testing, individual software modules are integrated logically and tested as a group.


A typical software project consists of multiple software modules, coded by different programmers.  Integration testing focuses on checking data communication amongst these modules.


Hence it is also termed as ‘I & T’ (Integration and Testing), ‘String Testing’ and sometimes ‘Thread Testing’.

Although each software module is unit tested, defects still exist for various reasons like,


  • A Module in general is designed by an individual software developer who understanding and programming logic may differ from other programmers. Integration testing becomes necessary to verify the software modules work in unity
  • At the time of module development, there wide chances of change in requirements by the clients. These new requirements may not be unit tested and hence integration testing becomes necessary.
  • Interfaces of the software modules with the database could be erroneous
  • External Hardware interfaces, if any, could be erroneous
  • Inadequate exception handling could cause issues.