Difference between system, Integration and E2E test?

System Testing, Integration Testing, E2E Testing:

1) System Testing:

• In System testing, testers test the complete  functionality of the application with respective client requirement.
• System testing is a black box testing.
• After completion of Component and Integration testing testers start System testing.
• System Testing done by professional Tester.

System testing mainly focus on 4 areas:

• Graphical User Interface Testing (GUI Testing)
• Functional Testing
• Non Functional Testing
• Usability Testing       

Advantages of System Testing:

• Verify the overall function of the System.
• Detects and identifies system level problem.
• Increase the system quality and reduce risk.
• Enhance overall performance of the system.

2) Integration Testing:

•   Integration testing performed between 2 or more modules.
•   It is a white box testing and developer will perform integration testing.
•   Integration testing focused on checking data communication between multiple modules.

Types of Integration Testing:

3)End to End Testing:

• End to end testing means validating the entire application along with all dependencies.
• In E2E testing we create an environment identical to the one that will be used by real users.
• In E2E we test all actions that users might perform their application.
• By using E2E testing we test entire flows.