What is System Testing?

• Testing the behavior of the entire(whole) software/system as defined in software requirements specification(SRS) is known as system testing.
• Its main focus is to verify that the customer requirements are fulfilled.
• System testing is done after integration testing is complete. 
• System testing should test functional and non functional requirements of the software.
• Testing done by a professional testing agent on the completed software product before it is introduced to the market.
• Some of the main testing types which need to be covered in system testing:
• Sanity Testing
• Usability Testing
• Stress Testing
• Load Testing
• Performance Testing
• Regression Testing
• Maintenance Testing
• Security Testing
• Accessibility Testing