Functional or behavioral testing checks whether the application behaves correctly based on requirements.
This includes testing both valid and invalid usage.
Positive Testing (Valid Use)
Tests what should work.
- Uses valid data
- Follows expected steps
- Includes:
- Happy Path – the most common way users will use the feature
- Alternate Paths – different valid ways to achieve the same result
If no data is involved, simply using the feature correctly counts as positive testing.
Negative Testing (Invalid Use)
Tests what should not work.
- Uses invalid data or incorrect steps
- Ensures the system:
- Doesn’t crash
- Displays helpful error messages
- Handles mistakes gracefully
Example:
Entering letters in a numeric field or skipping required steps.