Functional testing can be called as requirement testing also. During this test the testing team concentrate on every functionality of the project.Integration testing mean when performing testing any mismatch occurs they report to the development team, then the development team team makes modification and send the modified build to the test engineers. The test engineers perform the testing on this modified build which is called regression testing.
Functional Testing: Testing based on an analysis of the specification of the functionality of a component or system.
Integration Testing: Testing performed to expose defects in the interfaces and in the interactions between integrated components or systems. (Mostly executed after Functional Testing of component/module) So very obvious term emerged from this as 'Functional Integration' Functional Integration: An integration approach that combines the components or systems for the purpose of getting a basic functionality working early.