Unit Testing:

• Break down the product into its smallest testable units (e.g., functions, methods).

• Write tests for each unit to verify it performs as expected.

• Use automated testing frameworks (e.g., JUnit, pytest) for efficiency.

• Run unit tests during development to catch issues early.
  

Integration Testing:

• Identify modules or components that interact with each other.

• Develop test cases to verify these interactions work correctly.

• Use testing frameworks that support integration testing (e.g., TestNG, Mocha).

• Perform tests after unit testing to ensure components work together as intended.
  

System Testing:

• Test the complete, integrated product in an environment that simulates real-world usage.

• Develop end-to-end test scenarios that cover the entire system’s functionality.

• Conduct tests to verify the product meets all specified requirements.

• Use both manual and automated testing tools to ensure thorough coverage.